Phylogenetic distribution and evolutionary dynamics of the sex determination genes doublesex and transformer in insects.

Science.gov (United States)

Geuverink, E; Beukeboom, L W

2014-01-01

Sex determination in insects is characterized by a gene cascade that is conserved at the bottom but contains diverse primary signals at the top. The bottom master switch gene doublesex is found in all insects. Its upstream regulator transformer is present in the orders Hymenoptera, Coleoptera and Diptera, but has thus far not been found in Lepidoptera and in the basal lineages of Diptera. transformer is presumed to be ancestral to the holometabolous insects based on its shared domains and conserved features of autoregulation and sex-specific splicing. We interpret that its absence in basal lineages of Diptera and its order-specific conserved domains indicate multiple independent losses or recruitments into the sex determination cascade. Duplications of transformer are found in derived families within the Hymenoptera, characterized by their complementary sex determination mechanism. As duplications are not found in any other insect order, they appear linked to the haplodiploid reproduction of the Hymenoptera. Further phylogenetic analyses combined with functional studies are needed to understand the evolutionary history of the transformer gene among insects. © 2013 S. Karger AG, Basel.

A new component of the Nasonia sex determining cascade is maternally silenced and regulates transformer expression.

Science.gov (United States)

Verhulst, Eveline C; Lynch, Jeremy A; Bopp, Daniel; Beukeboom, Leo W; van de Zande, Louis

2013-01-01

Although sex determination is a universal process in sexually reproducing organisms, sex determination pathways are among the most highly variable genetic systems found in nature. Nevertheless, general principles can be identified among the diversity, like the central role of transformer (tra) in insects. When a functional TRA protein is produced in early embryogenesis, the female sex determining route is activated, while prevention of TRA production leads to male development. In dipterans, male development is achieved by prevention of female-specific splicing of tra mRNA, either mediated by X-chromosome dose or masculinizing factors. In Hymenoptera, which have haplodiploid sex determination, complementary sex determination and maternal imprinting have been identified to regulate timely TRA production. In the parasitoid Nasonia, zygotic transformer (Nvtra) expression and splicing is regulated by a combination of maternal provision of Nvtra mRNA and silencing of Nvtra expression in unfertilized eggs. It is unclear, however, if this silencing is directly on the tra locus or whether it is mediated through maternal silencing of a trans-acting factor. Here we show that in Nasonia, female sex determination is dependent on zygotic activation of Nvtra expression by an as yet unknown factor. This factor, which we propose to term womanizer (wom), is maternally silenced during oogenesis to ensure male development in unfertilized eggs. This finding implicates the upstream recruitment of a novel gene in the Nasonia sex determining cascade and supports the notion that sex determining cascades can rapidly change by adding new components on top of existing regulators.

A New Component of the Nasonia Sex Determining Cascade Is Maternally Silenced and Regulates Transformer Expression

Science.gov (United States)

Bopp, Daniel; Beukeboom, Leo W.; van de Zande, Louis

2013-01-01

Although sex determination is a universal process in sexually reproducing organisms, sex determination pathways are among the most highly variable genetic systems found in nature. Nevertheless, general principles can be identified among the diversity, like the central role of transformer (tra) in insects. When a functional TRA protein is produced in early embryogenesis, the female sex determining route is activated, while prevention of TRA production leads to male development. In dipterans, male development is achieved by prevention of female-specific splicing of tra mRNA, either mediated by X-chromosome dose or masculinizing factors. In Hymenoptera, which have haplodiploid sex determination, complementary sex determination and maternal imprinting have been identified to regulate timely TRA production. In the parasitoid Nasonia, zygotic transformer (Nvtra) expression and splicing is regulated by a combination of maternal provision of Nvtra mRNA and silencing of Nvtra expression in unfertilized eggs. It is unclear, however, if this silencing is directly on the tra locus or whether it is mediated through maternal silencing of a trans-acting factor. Here we show that in Nasonia, female sex determination is dependent on zygotic activation of Nvtra expression by an as yet unknown factor. This factor, which we propose to term womanizer (wom), is maternally silenced during oogenesis to ensure male development in unfertilized eggs. This finding implicates the upstream recruitment of a novel gene in the Nasonia sex determining cascade and supports the notion that sex determining cascades can rapidly change by adding new components on top of existing regulators. PMID:23717455

Sex selection and restricting abortion and sex determination.

Science.gov (United States)

Zilberberg, Julie

2007-11-01

Sex selection in India and China is fostered by a limiting social structure that disallows women from performing the roles that men perform, and relegates women to a lower status level. Individual parents and individual families benefit concretely from having a son born into the family, while society, and girls and women as a group, are harmed by the widespread practice of sex selection. Sex selection reinforces oppression of women and girls. Sex selection is best addressed by ameliorating the situations of women and girls, increasing their autonomy, and elevating their status in society. One might argue that restricting or prohibiting abortion, prohibiting sex selection, and prohibiting sex determination would eliminate sex selective abortion. But this decreases women's autonomy rather than increases it. Such practices will turn underground. Sex selective infanticide, and slower death by long term neglect, could increase. If abortion is restricted, the burden is placed on women seeking abortions to show that they have a legally acceptable or legitimate reason for a desired abortion, and this seriously limits women's autonomy. Instead of restricting abortion, banning sex selection, and sex determination, it is better to address the practice of sex selection by elevating the status of women and empowering women so that giving birth to a girl is a real and positive option, instead of a detriment to the parents and family as it is currently. But, if a ban on sex selective abortion or a ban on sex determination is indeed instituted, then wider social change promoting women's status in society should be instituted simultaneously.

Sex Determination, Sex Chromosomes, and Karyotype Evolution in Insects.

Science.gov (United States)

Blackmon, Heath; Ross, Laura; Bachtrog, Doris

2017-01-01

Insects harbor a tremendous diversity of sex determining mechanisms both within and between groups. For example, in some orders such as Hymenoptera, all members are haplodiploid, whereas Diptera contain species with homomorphic as well as male and female heterogametic sex chromosome systems or paternal genome elimination. We have established a large database on karyotypes and sex chromosomes in insects, containing information on over 13000 species covering 29 orders of insects. This database constitutes a unique starting point to report phylogenetic patterns on the distribution of sex determination mechanisms, sex chromosomes, and karyotypes among insects and allows us to test general theories on the evolutionary dynamics of karyotypes, sex chromosomes, and sex determination systems in a comparative framework. Phylogenetic analysis reveals that male heterogamety is the ancestral mode of sex determination in insects, and transitions to female heterogamety are extremely rare. Many insect orders harbor species with complex sex chromosomes, and gains and losses of the sex-limited chromosome are frequent in some groups. Haplodiploidy originated several times within insects, and parthenogenesis is rare but evolves frequently. Providing a single source to electronically access data previously distributed among more than 500 articles and books will not only accelerate analyses of the assembled data, but also provide a unique resource to guide research on which taxa are likely to be informative to address specific questions, for example, for genome sequencing projects or large-scale comparative studies. © The American Genetic Association 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Does the mechanism of sex determination constrain the potential for sex manipulation? A test in geckos with contrasting sex-determining systems

Science.gov (United States)

Kratochvíl, Lukáš; Kubička, Lukáš; Landová, Eva

2008-03-01

The concentration of yolk steroids was suggested to influence offspring gender in oviparous animals subject to both temperature-dependent sex determination (TSD) and genotypic sex determination (GSD). However, the proposed mechanisms of steroid effects are thought to differ between TSD and GSD: a direct effect of oestrogens on gonad feminisation in TSD species vs a differential induction of male-producing or female-producing gametes in GSD species. Geckos offer an ideal opportunity for testing these suggested mechanisms. Closely related gecko species differ in their modes of sex determination. They lay clutches of two synchronously formed eggs; both eggs share equal steroid levels. If identical hormonal composition and environment during vitellogenesis, gravidity and incubation determine the sex of the progeny, siblings should share the same gender in both TSD and GSD geckos. We found strong support for this prediction in a TSD gecko species. Among clutches that were incubated at the temperature that produced both sexes, there were no clutches with siblings of the opposite sex. On the other hand, about half of the clutches yielded siblings of the opposite sex in four GSD species. These results suggest that sex-determining systems constrain the ability of the female to produce single-sex siblings and, hence, it seems that the GSD mechanism constrains the opportunities for sex ratio manipulation in geckos via yolk steroid manipulation.

Determination of complementary therapies for prevention of striae gravidarum

Directory of Open Access Journals (Sweden)

Gamze Teskereci

2018-03-01

Full Text Available Background and Design: Striae gravidarum (SG has been reported to be associated with various factors, but the role of complementary therapies in the prevention of SG is still not well understood. The aim of this study was to determine complementary therapies for prevention of SG. Materials and Methods: This descriptive research was conducted on 120 pregnant women in a maternity clinic at a university hospital. Of 120 women, 49 were going through the last trimester and 71 were going through their first postpartum 24 hours. Data were collected using a 25-item-questionnaire through face-to-face interviews between June and July in 2016. Obtained data were evaluated by using descriptive statistics, chi-square test and the Kruskal-Wallis test. Results: 90.8% of women had SG. For the prevention of SG, 46.7% of women used massage, a manipulative body-based complementary therapy, 55.2% used oils, 28.6% used creams and 8.0% used a mixture of creams and oils for massaging. 42.9% of women started to use complementary therapies in their first trimester. Half of the women stated that they had received information about complementary therapies. A significantly lower rate of women using massage had SG compared to those not using massage (p=0.023. Conclusion: It was concluded that nearly half of the women used massage for the prevention of SG. In addition, massage application was found to reduce the occurrence of SG.

Vertebrate sex-determining genes play musical chairs.

Science.gov (United States)

Pan, Qiaowei; Anderson, Jennifer; Bertho, Sylvain; Herpin, Amaury; Wilson, Catherine; Postlethwait, John H; Schartl, Manfred; Guiguen, Yann

2016-01-01

Sexual reproduction is one of the most highly conserved processes in evolution. However, the genetic and cellular mechanisms making the decision of whether the undifferentiated gonad of animal embryos develops either towards male or female are manifold and quite diverse. In vertebrates, sex-determining mechanisms range from environmental to simple or complex genetic mechanisms and different mechanisms have evolved repeatedly and independently. In species with simple genetic sex-determination, master sex-determining genes lying on sex chromosomes drive the gonadal differentiation process by switching on a developmental program, which ultimately leads to testicular or ovarian differentiation. So far, very few sex-determining genes have been identified in vertebrates and apart from mammals and birds, these genes are apparently not conserved over a larger number of related orders, families, genera, or even species. To fill this knowledge gap and to better explore genetic sex-determination, we propose a strategy (RAD-Sex) that makes use of next-generation sequencing technology to identify genetic markers that define sex-specific segments of the male or female genome. Copyright © 2016 Académie des sciences. All rights reserved.

Sex determination in mythology and history.

Science.gov (United States)

Mittwoch, Ursula

2005-02-01

The history of ideas on how the sexes became divided spans at least three thousand years. The biblical account of the origin of Eve, and the opinions of the philosophers of classical Greece, have unexpected bearings on present-day ideas. The scientific study of sex determination can be said to have begun in the 17th century with the discovery of spermatozoa, but the origin and function of the "spermatic animalcules" eluded investigators until 1841. The mammalian egg was discovered in 1827, and in the last quarter of the century fertilization was observed. The view current at that time, that sex determination was under environmental control, gave way to the idea of chromosomal determination in the first quarter of the 20th century. The study of human and other mammalian chromosomes during the third quarter of the century, and the discovery of sex-chromosome abnormalities, emphasized the importance of the Y chromosome for male sex determination. The last quarter of the century witnessed a hunt for the "testis-determining" gene, thought to be responsible for the differentiation of Sertoli cells, and culminating in the isolation of SRY (Sry in the mouse). However, an increasing number of additional genes and growth factors were found to be required for the establishment of male sex. During the same period evidence emerged that male development was accompanied by enhanced growth, both of gonads and whole embryos. An unexpected finding was the demonstration of temperature-dependent sex determination in reptiles. With the advent of the 21st century, it was shown that Sry induces cell proliferation in fetal mouse gonads, and it has been suggested that male sex differentiation in mammals requires a higher metabolic rate. These insights could lead to a better understanding and improved treatment of abnormalities of sexual development.

Sex-determination systems and their evolution: Mammals

International Nuclear Information System (INIS)

Colorado Garzon, Fredy A; Matta Camacho, Nubia E; Sanchez, Antonio

2012-01-01

Sex-determination methods are very diverse as they have become an enduring research field, understanding the causes of gonadal development and elucidating the main factors involved in sex-determination of offspring required relating information from far-ranging areas such as cytology, embryology, morphology, molecular biology and even ecology and evolution. This article presents an overview of sex-determination in placental mammals, encompassing several levels of biological organization. The importance of the underlying molecular tools in the context of sex-determination assays and their implications in conservation genetics is also discussed.

Commentary Sex determination

Indian Academy of Sciences (India)

PRAKASH KUMAR G

2008-01-31

ZW is reserved for female heterogamety.) The Radder et al study used lab incubation regimes that mimic temperature profiles of cool natural nests, so temperature probably determines sex at least occasionally in nature.

Determination of sex by armbone dimensions.

Science.gov (United States)

Aye, Victor Omakoji

2010-06-15

Sex determination is a vital part of the medico-legal system but can be difficult in cases where the body is damaged. The purpose of this study was to develop a technique for sex determination from three arm-bone dimensions (wrist circumference, arm length and arm span). This knowledge can be applied in cases of mass disaster, homicide and events such as sports. Data were collected for 95 Nigerian male students and 90 Nigerian female students using physical anthropometry. Discriminant function presented the wrist dimension as the dominant contributor in this study. Combination equations for both the wrist and arm-span dimensions correctly classified sex (male/female) with an accuracy rate of 84.9%. On cross-validation, sex was also established with the same 84.9% accuracy rate. Sex determination was higher in males. Sexual dimorphism was established in this study, although the wrist circumference was more distinct than arm span; a combination of both generated sex with an accuracy prediction rate of 84.9%. (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Embryonic origin of mate choice in a lizard with temperature-dependent sex determination.

Science.gov (United States)

Putz, Oliver; Crews, David

2006-01-01

Individual differences in the adult sexual behavior of vertebrates are rooted in the fetal environment. In the leopard gecko (Eublepharis macularius), a species with temperature-dependent sex determination (TSD), hatchling sex ratios differ between incubation temperatures, as does sexuality in same-sex animals. This variation can primarily be ascribed to the temperature having direct organizing actions on the brain. Here we demonstrate that embryonic temperature can affect adult mate choice in the leopard gecko. Given the simultaneous choice between two females from different incubation temperatures (30.0 and 34.0 degrees C), males from one incubation temperature (30.0 degrees C) preferred the female from 34.0 degrees C, while males from another incubation temperature (32.5 degrees C) preferred the female from 30.0 degrees C. We suggest that this difference in mate choice is due to an environmental influence on brain development leading to differential perception of opposite-sex individuals. This previously unrecognized modulator of adult mate choice lends further support to the view that mate choice is best understood in the context of an individual's entire life-history. Thus, sexual selection results from a combination of the female's as well as the male's life history. Female attractiveness and male choice therefore are complementary. Copyright 2005 Wiley Periodicals, Inc.

Determinants of public trust in complementary and alternative medicine

NARCIS (Netherlands)

Schee, E. van der; Groenewegen, P.P.

2010-01-01

Background: In the Netherlands, public trust in conventional medicine is relatively high. There is reason to believe that public trust in complementary and alternative medicine (CAM) is rated lower. The aim of this study is to gain insight into public trust in CAM and the determinants that lie at

Complementary and Alternative Medicines: Usage and Its Determinant Factors Among Outpatients in Southeast of Iran.

Science.gov (United States)

Ghaedi, Fateme; Dehghan, Mahlagha; Salari, Masoumeh; Sheikhrabori, Akbar

2015-12-13

Prevalence of complementary and alternative medicines is increasing specially in patients with chronic diseases. Therefore, based on the high prevalence of chronic disorders, the present study aimed to determine complementary and alternative medicine usage frequency and its determinant factors. This was a cross-sectional study. Five hundred clients participated in the study by using convenience sampling. A 2-part questionnaire (including demographic form and researcher-created questionnaire) was used for studying the prevalence of using complementary and alternative medicine methods, and users' satisfaction. Findings showed that 75.4% of people used at least one complementary and alternative medicine method. Most of users consumed medicinal plants (69.4%). The most common reason of using a complementary and alternative medicine method was common cold (32.9%). The highest satisfaction belonged to massage (2.94 ± 0.74). The usage of complementary and alternative medicine was 3.22 times higher in people with academic educations when compared with illiterate people. Concerning the high usage of complementary and alternative medicine, it is necessary to train specialists in this field in order to offer such treatments in a safe manner. Also, outcomes of application of complementary and alternative medicine methods should be studied. © The Author(s) 2015.

Using technology, choosing sex. The campaign against sex determination and the question of choice.

Science.gov (United States)

1992-01-01

Women's groups and people's science and health groups formed the Forum Against Sex Determination and Sex Pre-Selection in November 1985 in Bombay, India, to prevent sex determination and sex preselection tests. The Forum considered sex determination and sex preselection to be an abuse of science and technology against people, especially women. Between 1901 and 1991, the sex ratio fell from 972 females/1000 males to 929/1000. The Forum saw the issue of sex determination and sex preselection as a link to oppression of and discrimination against females in all sectors of society. It also believed this to be a human rights issue. The Forum lobbied for a law regulating diagnostic techniques without banning them, since determining chromosomal abnormalities is important. The State of Maharashtra passed such a law in June 1988. It had some provisions which were counter-productive, however. For example, women undergoing a sex determination test must pay a fine of Rs 5 if found guilty of planning to terminate a pregnancy of a female fetus. Yet, neither the husband nor parents-in-law are liable, even though they often pressure women to undergo sex determination tests. The Forum's efforts and enactment of the law in Maharashtra have prompted other state governments and the central government to propose similar legislation. These state governments include Goa, Gujarat, and Orissa. The central government has met with organizations and individuals lobbying against misuse of diagnostic tests to obtain their counsel. The Forum does not feel comfortable with state control, however, since it tends to consider government to be against the people. Yet, the Forum did want the state to protect women's interests. It has raised important questions about technology, particularly concerning criteria to determine desirable and appropriate technologies.

Insect sex determination: it all evolves around transformer.

Science.gov (United States)

Verhulst, Eveline C; van de Zande, Louis; Beukeboom, Leo W

2010-08-01

Insects exhibit a variety of sex determining mechanisms including male or female heterogamety and haplodiploidy. The primary signal that starts sex determination is processed by a cascade of genes ending with the conserved switch doublesex that controls sexual differentiation. Transformer is the doublesex splicing regulator and has been found in all examined insects, indicating its ancestral function as a sex-determining gene. Despite this conserved function, the variation in transformer nucleotide sequence, amino acid composition and protein structure can accommodate a multitude of upstream sex determining signals. Transformer regulation of doublesex and its taxonomic distribution indicate that the doublesex-transformer axis is conserved among all insects and that transformer is the key gene around which variation in sex determining mechanisms has evolved.

The accuracy of 2D ultrasound prenatal sex determination ...

African Journals Online (AJOL)

Most of the women were happy even when the sex differed from that which they desired. Conclusion: Prenatal sonographic sex determination has a high sensitivity index. Consequently we advocate its use prior to more invasive sex tests. Keywords: Accuracy, gender determination, prenatal gender, prenatal sex, sex ...

Complementary and alternative medicine usage and its determinant factors among Iranian infertile couples.

Science.gov (United States)

Dehghan, Mahlagha; Mokhtarabadi, Sima; Heidari, Fatemeh Ghaedi

2018-04-04

Background The aim of this study was to determine the status of utilizing some complementary and alternative medicine techniques in infertile couples. Methods This was a cross-sectional study conducted on 250 infertile couples referred to a hospital in Kerman using convenience sampling. A researcher-made questionnaire was used to study the prevalence and user satisfaction of complementary and alternative medicines. Results Results indicated that 49.6% of the infertile couples used at least one of the complementary and alternative medicines during the past year. Most individuals used spiritual techniques (71.8% used praying and 70.2% used Nazr) and medicinal plants (54.8%). Safety is the most important factor affecting the satisfaction of infertile couples with complementary treatments (couples think that such treatments are safe (54.8%)). Discussion Concerning high prevalence of complementary and alternative treatments in infertile couples, incorporating such treatments into the healthcare education and promoting the awareness of infertile individuals seem crucial.

Sex Determination, Sex Ratios, and Genetic Conflict

NARCIS (Netherlands)

Werren, John H.; Beukeboom, Leo W.

1998-01-01

Genetic mechanisms of sex determination are unexpectedly diverse and change rapidly during evolution. We review the role of genetic conflict as the driving force behind this diversity and turnover. Genetic conflict occurs when different components of a genetic system are subject to selection in

Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses.

Science.gov (United States)

Argue, Kathryn J; Neckameyer, Wendi S

2014-07-01

The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. Copyright © 2014 the American Physiological Society.

Maternal provision of non-sex-specific transformer messenger RNA in sex determination of the wasp Asobara tabida.

Science.gov (United States)

Geuverink, E; Verhulst, E C; van Leussen, M; van de Zande, L; Beukeboom, L W

2018-02-01

In many insect species maternal provision of sex-specifically spliced messenger RNA (mRNA) of sex determination genes is an essential component of the sex determination mechanism. In haplodiploid Hymenoptera, maternal provision in combination with genomic imprinting has been shown for the parasitoid Nasonia vitripennis, known as maternal effect genomic imprinting sex determination (MEGISD). Here, we characterize the sex determination cascade of Asobara tabida, another hymenopteran parasitoid. We show the presence of the conserved sex determination genes doublesex (dsx), transformer (tra) and transformer-2 (tra2) orthologues in As. tabida. Of these, At-dsx and At-tra are sex-specifically spliced, indicating a conserved function in sex determination. At-tra and At-tra2 mRNA is maternally provided to embryos but, in contrast to most studied insects, As. tabida females transmit a non-sex-specific splice form of At-tra mRNA to the eggs. In this respect, As. tabida sex determination differs from the MEGISD mechanism. How the paternal genome can induce female development in the absence of maternal provision of sex-specifically spliced mRNA remains an open question. Our study reports a hitherto unknown variant of maternal effect sex determination and accentuates the diversity of insect sex determination mechanisms. © 2017 The Authors. Insect Molecular Biology published by John Wiley & Sons Ltd on behalf of Royal Entomological Society.

A Review of Sex Determining Mechanisms in Geckos (Gekkota: Squamata)

OpenAIRE

Gamble, T.

2010-01-01

Geckos are a species-rich clade of reptiles possessing diverse sex determining mechanisms. Some species possess genetic sex determination, with both male and female heterogamety, while other species have temperature-dependent sex determination. I compiled information from the literature on the taxonomic distribution of these sex determining mechanisms in geckos. Using phylogenetic data from the literature, I reconstructed the minimum number of transitions among these sex determining mechanism...

A Review of Sex Determining Mechanisms in Geckos (Gekkota: Squamata)

Science.gov (United States)

Gamble, T.

2010-01-01

Geckos are a species-rich clade of reptiles possessing diverse sex determining mechanisms. Some species possess genetic sex determination, with both male and female heterogamety, while other species have temperature-dependent sex determination. I compiled information from the literature on the taxonomic distribution of these sex determining mechanisms in geckos. Using phylogenetic data from the literature, I reconstructed the minimum number of transitions among these sex determining mechanisms with parsimony-based ancestral state reconstruction. While only a small number of gecko species have been characterized, numerous changes among sex determining mechanisms were inferred. This diversity, coupled with the high frequency of transitions, makes geckos excellent candidates as a model clade for the study of vertebrate sex determination and evolution. PMID:20234154

[Elucidation of key genes in sex determination in genetics teaching].

Science.gov (United States)

Li, Meng; He, Zhumei

2014-06-01

Sex is an important and complex feature of organisms, which is controlled by the genetic and environmental factors. The genetic factors, i.e., genes, are vital in sex determination. However, not all the related genes play the same roles, and some key genes play a vital role in the sex determination and differentiation. With the development of the modern genetics, a great progress on the key genes has been made in sex determination. In this review, we summarize the mechanism of sex determination and the strategy of how to study the key genes in sex determination. It will help us to understand the mechanism of sex determination better in the teaching of genetics.

Sex Determination: Why So Many Ways of Doing It?

Science.gov (United States)

Bachtrog, Doris; Mank, Judith E.; Peichel, Catherine L.; Kirkpatrick, Mark; Otto, Sarah P.; Ashman, Tia-Lynn; Hahn, Matthew W.; Kitano, Jun; Mayrose, Itay; Ming, Ray; Perrin, Nicolas; Ross, Laura; Valenzuela, Nicole; Vamosi, Jana C.

2014-01-01

Sexual reproduction is an ancient feature of life on earth, and the familiar X and Y chromosomes in humans and other model species have led to the impression that sex determination mechanisms are old and conserved. In fact, males and females are determined by diverse mechanisms that evolve rapidly in many taxa. Yet this diversity in primary sex-determining signals is coupled with conserved molecular pathways that trigger male or female development. Conflicting selection on different parts of the genome and on the two sexes may drive many of these transitions, but few systems with rapid turnover of sex determination mechanisms have been rigorously studied. Here we survey our current understanding of how and why sex determination evolves in animals and plants and identify important gaps in our knowledge that present exciting research opportunities to characterize the evolutionary forces and molecular pathways underlying the evolution of sex determination. PMID:24983465

Sex determination based on amelogenin DNA by modified electrode with gold nanoparticle.

Science.gov (United States)

Mazloum-Ardakani, Mohammad; Rajabzadeh, Nooshin; Benvidi, Ali; Heidari, Mohammad Mehdi

2013-12-15

We have developed a simple and renewable electrochemical biosensor based on carbon paste electrode (CPE) for the detection of DNA synthesis and hybridization. CPE was modified with gold nanoparticles (AuNPs), which are helpful for immobilization of thiolated bioreceptors. AuNPs were characterized by scanning electron microscopy (SEM). Self-assembled monolayers (SAMs) of thiolated single-stranded DNA (SH-ssDNA) of the amelogenin gene was formed on CPE. The immobilization of the probe and its hybridization with the target DNA was optimized using different experimental conditions. The modified electrode was characterized by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The electrochemical response of ssDNA hybridization and DNA synthesis was measured using differential pulse voltammetry (DPV) with methylene blue (MB) as an electroactive indicator. The new biosensor can distinguish between complementary and non-complementary strands of amelogenin ssDNA. Genomic DNA was extracted from blood and was detected based on changes in the MB reduction signal. These results demonstrated that the new biosensor could be used for sex determination. The proposed biosensor in this study could be used for detection and discrimination of polymerase chain reaction (PCR) products of amelogenin DNA. Copyright © 2013 Elsevier Inc. All rights reserved.

What was the ancestral sex-determining mechanism in amniote vertebrates?

Science.gov (United States)

Johnson Pokorná, Martina; Kratochvíl, Lukáš

2016-02-01

Amniote vertebrates, the group consisting of mammals and reptiles including birds, possess various mechanisms of sex determination. Under environmental sex determination (ESD), the sex of individuals depends on the environmental conditions occurring during their development and therefore there are no sexual differences present in their genotypes. Alternatively, through the mode of genotypic sex determination (GSD), sex is determined by a sex-specific genotype, i.e. by the combination of sex chromosomes at various stages of differentiation at conception. As well as influencing sex determination, sex-specific parts of genomes may, and often do, develop specific reproductive or ecological roles in their bearers. Accordingly, an individual with a mismatch between phenotypic (gonadal) and genotypic sex, for example an individual sex-reversed by environmental effects, should have a lower fitness due to the lack of specialized, sex-specific parts of their genome. In this case, evolutionary transitions from GSD to ESD should be less likely than transitions in the opposite direction. This prediction contrasts with the view that GSD was the ancestral sex-determining mechanism for amniote vertebrates. Ancestral GSD would require several transitions from GSD to ESD associated with an independent dedifferentiation of sex chromosomes, at least in the ancestors of crocodiles, turtles, and lepidosaurs (tuataras and squamate reptiles). In this review, we argue that the alternative theory postulating ESD as ancestral in amniotes is more parsimonious and is largely concordant with the theoretical expectations and current knowledge of the phylogenetic distribution and homology of sex-determining mechanisms. © 2014 Cambridge Philosophical Society.

Microbial manipulation of host sex determination

NARCIS (Netherlands)

Beukeboom, Leo W.

A recent study in the lepidopteran Ostrinia scapulalis shows that endosymbionts can actively manipulate the sex determination mechanism of their host. Wolbachia bacteria alter the sex-specific splicing of the doublesex master switch gene. In ZZ males of this female heterogametic system, the female

Sex determination mechanisms in the Calliphoridae (blow flies).

Science.gov (United States)

Scott, M J; Pimsler, M L; Tarone, A M

2014-01-01

The Calliphoridae or blow flies are a family of insects that occupy diverse habitats and perform important ecological roles, particularly the decomposition of animal remains. Some Calliphoridae species are also important in the forensic sciences, in agriculture (e.g. as livestock pests) and in medicine (e.g. maggot therapy). Calliphoridae provide striking examples in support of the hypothesis that sex determination regulatory gene hierarchies evolve in the reverse order, with the gene at the top being the most recently added. Unlike the model fly Drosophila melanogaster, where sex is determined by the number of X chromosomes, in the Australian sheep blow fly (Lucilia cuprina) sex is determined by a Y-linked male-determining gene (M). A different regulatory system appears to operate in the hairy maggot blow fly (Chrysomya rufifacies) where the maternal genotype determines sex. It is hypothesized that females heterozygous for a dominant female-determining factor (F/f) produce only female offspring and homozygous f/f females produce only sons. The bottom of the regulatory hierarchy appears to be the same in D. melanogaster and L. cuprina, with sex-specific splicing of doublesex transcripts being controlled by the female-specific Transformer (TRA) protein. We discuss a model that has been proposed for how tra transcripts are sex-specifically spliced in calliphorids, which is very different from D. melanogaster. © 2013 S. Karger AG, Basel.

Longevity enhances selection of environmental sex determination.

Science.gov (United States)

Bull, J J; Bulmer, M G

1989-12-01

Environmental sex determination (ESD) is a mechanism in which an individual develops as male or female largely in response to some environmental effect experienced early in life. Its forms range from sex determination by egg incubation temperature in reptiles to sex determination of photoperiod in amphipods. Previous theoretical work as suggested that ESD is favored by natural selection if the fitness consequences of the early environmental experience differ for males and females, so that an individual benefits by being male under some conditions and female under others. A drawback of ESD is that it enables climatic changes to influence the population sex ratio, and such fluctuations select against ESD. This study employed numerical analyses to investigate the balance between these two opposing forces. The negative impact of climatic fluctuations appears to depend greatly on species longevity: substantial between-year fluctuations are of little consequence in selecting against ESD in long-lived species because annual sex ratio fluctuations tend to cancel and thus alter the total population sex ratio only slightly. Thus, if a species is sufficiently long-lived, extreme ESD can be maintained despite only a weak advantage. This result offers one explanation for the failure to demonstrate an advantage for the extreme forms of ESD observed in reptiles.

Conflict over condition-dependent sex allocation can lead to mixed sex-determination systems

NARCIS (Netherlands)

Kuijper, Bram; Pen, Ido

Theory suggests that genetic conflicts drive turnovers between sex-determining mechanisms, yet these studies only apply to cases where sex allocation is independent of environment or condition. Here, we model parent-offspring conflict in the presence of condition-dependent sex allocation, where the

Conflict over condition-dependent sex allocation can lead to mixed sex-determination systems

NARCIS (Netherlands)

Kuijper, Bram; Pen, Ido

2014-01-01

Theory suggests that genetic conflicts drive turnovers between sex-determining mechanisms, yet these studies only apply to cases where sex allocation is independent of environment or condition. Here, we model parent-offspring conflict in the presence of condition-dependent sex allocation, where the

Transitions between sex-determining systems in reptiles and amphibians.

Science.gov (United States)

Sarre, Stephen D; Ezaz, Tariq; Georges, Arthur

2011-01-01

Important technological advances in genomics are driving a new understanding of the evolution of sex determination in vertebrates. In particular, comparative chromosome mapping in reptiles has shown an intriguing distribution of homology in sex chromosomes across reptile groups. When this new understanding is combined with the widespread distribution of genetic and temperature-dependent sex-determination mechanisms among reptiles, it is apparent that transitions between modes have occurred many times, as they have for amphibians (particularly between male and female heterogamety). It is also likely that thermosensitivity in sex determination is a key factor in those transitions in reptiles, and possibly in amphibians too. New models of sex determination involving temperature thresholds are providing the framework for the investigation of transitions and making possible key predictions about the homologies and sex-determination patterns expected among taxa in these groups. Molecular cytogenetics and other genomic approaches are essential to providing the fundamental material necessary to make advances in this field.

Cretaceous park of sex determination: sex chromosomes are conserved across iguanas.

Science.gov (United States)

Rovatsos, Michail; Pokorná, Martina; Altmanová, Marie; Kratochvíl, Lukáš

2014-03-01

Many poikilothermic vertebrate lineages, especially among amphibians and fishes, possess a rapid turnover of sex chromosomes, while in endotherms there is a notable stability of sex chromosomes. Reptiles in general exhibit variability in sex-determining systems; as typical poikilotherms, they might be expected to have a rapid turnover of sex chromosomes. However, molecular data which would enable the testing of the stability of sex chromosomes are lacking in most lineages. Here, we provide molecular evidence that sex chromosomes are highly conserved across iguanas, one of the most species-rich clade of reptiles. We demonstrate that members of the New World families Iguanidae, Tropiduridae, Leiocephalidae, Phrynosomatidae, Dactyloidae and Crotaphytidae, as well as of the family Opluridae which is restricted to Madagascar, all share homologous sex chromosomes. As our sampling represents the majority of the phylogenetic diversity of iguanas, the origin of iguana sex chromosomes can be traced back in history to the basal splitting of this group which occurred during the Cretaceous period. Iguanas thus show a stability of sex chromosomes comparable to mammals and birds and represent the group with the oldest sex chromosomes currently known among amniotic poikilothermic vertebrates.

Climate-driven population divergence in sex-determining systems

NARCIS (Netherlands)

Pen, Ido; Uller, Tobias; Feldmeyer, Barbara; Harts, Anna; While, Geoffrey M.; Wapstra, Erik

2010-01-01

Sex determination is a fundamental biological process, yet its mechanisms are remarkably diverse(1,2). In vertebrates, sex can be determined by inherited genetic factors or by the temperature experienced during embryonic development(2,3). However, the evolutionary causes of this diversity remain

Insect sex determination : It all evolves around transformer

NARCIS (Netherlands)

Verhulst, Eveline C.; van de Zande, Louis; Beukeboom, Leo W.

Insects exhibit a variety of sex determining mechanisms including male or female heterogamety and haplodiploidy. The primary signal that starts sex determination is processed by a cascade of genes ending with the conserved switch doublesex that controls sexual differentiation. Transformer is the

Genetics of sex determination in the haplodiploid wasp Nasonia ...

Indian Academy of Sciences (India)

2010-09-06

Sep 6, 2010 ... How gender is determined under haplodiploidy in the ab- sence of heteromorphic sex ... determination (see below). Sex-determination mutants ... not others (Nöthiger and Steinmann-Zwicky 1985; Wilkins. 1995; Saccone et al.

Patterns and determinants of breastfeeding and complementary feeding practices in urban informal settlements, Nairobi Kenya.

Science.gov (United States)

Kimani-Murage, Elizabeth W; Madise, Nyovani J; Fotso, Jean-Christophe; Kyobutungi, Catherine; Mutua, Martin K; Gitau, Tabither M; Yatich, Nelly

2011-05-26

The World Health Organisation (WHO) recommends exclusive breastfeeding during the first six months of life for optimal growth, development and health. Breastfeeding should continue up to two years or more and nutritionally adequate, safe, and appropriately-fed complementary foods should be introduced at the age of six months to meet the evolving needs of the growing infant. Little evidence exists on breastfeeding and infant feeding practices in urban slums in sub-Saharan Africa. Our aim was to assess breastfeeding and infant feeding practices in Nairobi slums with reference to WHO recommendations. Data from a longitudinal study conducted in two Nairobi slums are used. The study used information on the first year of life of 4299 children born between September 2006 and January 2010. All women who gave birth during this period were interviewed on breastfeeding and complementary feeding practices at recruitment and this information was updated twice, at four-monthly intervals. Cox proportional hazard analysis was used to determine factors associated with cessation of breastfeeding in infancy and early introduction of complementary foods. There was universal breastfeeding with almost all children (99%) having ever been breastfed. However, more than a third (37%) were not breastfed in the first hour following delivery, and 40% were given something to drink other than the mothers' breast milk within 3 days after delivery. About 85% of infants were still breastfeeding by the end of the 11th month. Exclusive breastfeeding for the first six months was rare as only about 2% of infants were exclusively breastfed for six months. Factors associated with sub-optimal infant breastfeeding and feeding practices in these settings include child's sex; perceived size at birth; mother's marital status, ethnicity; education level; family planning (pregnancy desirability); health seeking behaviour (place of delivery) and; neighbourhood (slum of residence). The study indicates poor

SEX DETERMINATION FROM FEMORAL HEAD DIAMETERS IN ...

African Journals Online (AJOL)

hi-tech

2000-03-01

Mar 1, 2000 ... In medico-legal cases where sophisticated methods of sex determination is lacking, these ... scientific methods(3). Using the visual method ... between the sexes and the values of the right and left femoral head diameters.

Environmental sex determination in the branchiopod crustacean Daphnia magna: deep conservation of a Doublesex gene in the sex-determining pathway.

Directory of Open Access Journals (Sweden)

Yasuhiko Kato

2011-03-01

Full Text Available Sex-determining mechanisms are diverse among animal lineages and can be broadly divided into two major categories: genetic and environmental. In contrast to genetic sex determination (GSD, little is known about the molecular mechanisms underlying environmental sex determination (ESD. The Doublesex (Dsx genes play an important role in controlling sexual dimorphism in genetic sex-determining organisms such as nematodes, insects, and vertebrates. Here we report the identification of two Dsx genes from Daphnia magna, a freshwater branchiopod crustacean that parthenogenetically produces males in response to environmental cues. One of these genes, designated DapmaDsx1, is responsible for the male trait development when expressed during environmental sex determination. The domain organization of DapmaDsx1 was similar to that of Dsx from insects, which are thought to be the sister group of branchiopod crustaceans. Intriguingly, the molecular basis for sexually dimorphic expression of DapmaDsx1 is different from that of insects. Rather than being regulated sex-specifically at the level of pre-mRNA splicing in the coding region, DapmaDsx1 exhibits sexually dimorphic differences in the abundance of its transcripts. During embryogenesis, expression of DapmaDsx1 was increased only in males and its transcripts were primarily detected in male-specific structures. Knock-down of DapmaDsx1 in male embryos resulted in the production of female traits including ovarian maturation, whereas ectopic expression of DapmaDsx1 in female embryos resulted in the development of male-like phenotypes. Expression patterns of another D. magna Dsx gene, DapmaDsx2, were similar to those of DapmaDsx1, but silencing and overexpression of this gene did not induce any clear phenotypic changes. These results establish DapmaDsx1 as a key regulator of the male phenotype. Our findings reveal how ESD is implemented by selective expression of a fundamental genetic component that is

Sex Determination in Insects: a binary decision based on alternative splicing

OpenAIRE

Salz, Helen K.

2011-01-01

The gene regulatory networks that control sex determination vary between species. Despite these differences, comparative studies in insects have found that alternative splicing is reiteratively used in evolution to control expression of the key sex determining genes. Sex determination is best understood in Drosophila where activation of the RNA binding protein encoding gene Sex-lethal is the central female-determining event. Sex-lethal serves as a genetic switch because once activated it cont...

Pet birds II. Complementary diagnostic procedures

International Nuclear Information System (INIS)

Beregi, A.; Molnar, V.; Felkai, F.; Biro, F.

1997-01-01

Microscopical examinations are useful in detecting bacteria from droppings and body fluids. Antimicrobial susceptibility tests are also used to perform antimicrobial therapy. Parasitological examinations can also be done on pet birds. Hematological examinations are not very common because of the difficulties in determining the normal serum values that might vary by species and sexes. The vena cutanea ulnaris is the best vein for drawing blood from a pet bird but nail clipping for this purpose is also widely used. The most common and basic complementary examination method is radiology. Birds can be radiographed without anesthesia. Ventrodorsal and latero-lateral pictures are required. The right positioning and setting the adequate values is the most important. Contrast radiographs can also be made on birds. Endoscopy is widely used for sex determination but also can be used for the examination of abdominal organs. Ultrasound examination of pet birds is not a common method because of the difficulties provided by the air sacs. ECG is not a widely used method either because of the high heart beat frequency of birds. Other methods such as necropsy, cytological, histological and toxicological examinations can also be performed on pet birds

Sex ratio selection and multi-factorial sex determination in the housefly : A dynamic model

NARCIS (Netherlands)

Kozielska, M.A.; Pen, I.R.; Beukeboom, L.W.; Weissing, F.J.

Sex determining (SD) mechanisms are highly variable between different taxonomic groups and appear to change relatively quickly during evolution. Sex ratio selection could be a dominant force causing such changes. We investigate theoretically the effect of sex ratio selection on the dynamics of a

Genotypic sex determination enabled adaptive radiations of extinct marine reptiles.

Science.gov (United States)

Organ, Chris L; Janes, Daniel E; Meade, Andrew; Pagel, Mark

2009-09-17

Adaptive radiations often follow the evolution of key traits, such as the origin of the amniotic egg and the subsequent radiation of terrestrial vertebrates. The mechanism by which a species determines the sex of its offspring has been linked to critical ecological and life-history traits but not to major adaptive radiations, in part because sex-determining mechanisms do not fossilize. Here we establish a previously unknown coevolutionary relationship in 94 amniote species between sex-determining mechanism and whether a species bears live young or lays eggs. We use that relationship to predict the sex-determining mechanism in three independent lineages of extinct Mesozoic marine reptiles (mosasaurs, sauropterygians and ichthyosaurs), each of which is known from fossils to have evolved live birth. Our results indicate that each lineage evolved genotypic sex determination before acquiring live birth. This enabled their pelagic radiations, where the relatively stable temperatures of the open ocean constrain temperature-dependent sex determination in amniote species. Freed from the need to move and nest on land, extreme physical adaptations to a pelagic lifestyle evolved in each group, such as the fluked tails, dorsal fins and wing-shaped limbs of ichthyosaurs. With the inclusion of ichthyosaurs, mosasaurs and sauropterygians, genotypic sex determination is present in all known fully pelagic amniote groups (sea snakes, sirenians and cetaceans), suggesting that this mode of sex determination and the subsequent evolution of live birth are key traits required for marine adaptive radiations in amniote lineages.

Rapid quantification and sex determination of forensic evidence materials.

Science.gov (United States)

Andréasson, Hanna; Allen, Marie

2003-11-01

DNA quantification of forensic evidence is very valuable for an optimal use of the available biological material. Moreover, sex determination is of great importance as additional information in criminal investigations as well as in identification of missing persons, no suspect cases, and ancient DNA studies. While routine forensic DNA analysis based on short tandem repeat markers includes a marker for sex determination, analysis of samples containing scarce amounts of DNA is often based on mitochondrial DNA, and sex determination is not performed. In order to allow quantification and simultaneous sex determination on minute amounts of DNA, an assay based on real-time PCR analysis of a marker within the human amelogenin gene has been developed. The sex determination is based on melting curve analysis, while an externally standardized kinetic analysis allows quantification of the nuclear DNA copy number in the sample. This real-time DNA quantification assay has proven to be highly sensitive, enabling quantification of single DNA copies. Although certain limitations were apparent, the system is a rapid, cost-effective, and flexible assay for analysis of forensic casework samples.

Sex determination in insects: a binary decision based on alternative splicing.

Science.gov (United States)

Salz, Helen K

2011-08-01

The gene regulatory networks that control sex determination vary between species. Despite these differences, comparative studies in insects have found that alternative splicing is reiteratively used in evolution to control expression of the key sex-determining genes. Sex determination is best understood in Drosophila where activation of the RNA binding protein-encoding gene Sex-lethal is the central female-determining event. Sex-lethal serves as a genetic switch because once activated it controls its own expression by a positive feedback splicing mechanism. Sex fate choice in is also maintained by self-sustaining positive feedback splicing mechanisms in other dipteran and hymenopteran insects, although different RNA binding protein-encoding genes function as the binary switch. Studies exploring the mechanisms of sex-specific splicing have revealed the extent to which sex determination is integrated with other developmental regulatory networks. Copyright © 2011 Elsevier Ltd. All rights reserved.

Occupational Segregation by Sex: Determinants and Changes.

Science.gov (United States)

Beller, Andrea H.

1982-01-01

This study found that occupational sex segregation began to diminish during the 1970s, in conjunction with enforcement of the equal employment opportunity laws against sex discrimination in employment. The success of these laws suggests that discrimination was originally a determinant of occupational segregation. (Author/SK)

Evidence of oligogenic sex determination in the apple snail Pomacea canaliculata.

Science.gov (United States)

Yusa, Yoichi; Kumagai, Natsumi

2018-02-26

A small number of genes may interact to determine sex, but few such examples have been demonstrated in animals, especially through comprehensive mating experiments. The highly invasive apple snail Pomacea canaliculata is gonochoristic and shows a large variation in brood sex ratio, and the involvement of multiple genes has been suggested for this phenomenon. We conducted mating experiments to determine whether their sex determination involves a few or many genes (i.e., oligogenic or polygenic sex determination, respectively). Full-sib females or males that were born from the same parents were mated to an adult of the opposite sex, and the brood sex ratios of the parents and their offspring were investigated. Analysis of a total of 4288 offspring showed that the sex ratios of offspring from the full-sib females were variable but clustered into only a few values. Similar patterns were observed for the full-sib males, although the effect was less clear because fewer offspring were used (n = 747). Notably, the offspring sex ratios of all full-sib females in some families were nearly 0.5 (proportion of males) with little variation. These results indicate that the number of genotypes of the full-sibs, and hence genes involved in sex determination, is small in this snail. Such oligogenic systems may be a major sex-determining system among animals, especially those with variable sex ratios.

Evolutionary diversity and turn-over of sex determination in teleost fishes.

Science.gov (United States)

Mank, J E; Avise, J C

2009-01-01

Sex determination, due to the obvious association with reproduction and Darwinian fitness, has been traditionally assumed to be a relatively conserved trait. However, research on teleost fishes has shown that this need not be the case, as these animals display a remarkable diversity in the ways that they determine sex. These different mechanisms, which include constitutive genetic mechanisms on sex chromosomes, polygenic constitutive mechanisms, environmental influences, hermaphroditism, and unisexuality have each originated numerous independent times in the teleosts. The evolutionary lability of sex determination, and the corresponding rapid rate of turn-over among different modes, makes the teleost clade an excellent model with which to test theories regarding the evolution of sex determining adaptations. Much of the plasticity in sex determination likely results from the dynamic teleost genome, and recent advances in fish genetics and genomics have revealed the role of gene and genome duplication in fostering emergence and turn-over of sex determining mechanisms. 2009 S. Karger AG, Basel.

Sex determination in the Hymenoptera

NARCIS (Netherlands)

Heimpel, George E.; de Boer, Jetske G.

2008-01-01

The dominant and ancestral mode of sex determination in the Hymenoptera is arrhenotokous parthenogenesis, in which diploid females develop from fertilized eggs and haploid males develop from unfertilized eggs. We discuss recent progress in the understanding of the genetic and cytoplasmic mechanisms

Patterns and determinants of breastfeeding and complementary feeding practices in urban informal settlements, Nairobi Kenya

Directory of Open Access Journals (Sweden)

Mutua Martin K

2011-05-01

Full Text Available Abstract Background The World Health Organisation (WHO recommends exclusive breastfeeding during the first six months of life for optimal growth, development and health. Breastfeeding should continue up to two years or more and nutritionally adequate, safe, and appropriately-fed complementary foods should be introduced at the age of six months to meet the evolving needs of the growing infant. Little evidence exists on breastfeeding and infant feeding practices in urban slums in sub-Saharan Africa. Our aim was to assess breastfeeding and infant feeding practices in Nairobi slums with reference to WHO recommendations. Methods Data from a longitudinal study conducted in two Nairobi slums are used. The study used information on the first year of life of 4299 children born between September 2006 and January 2010. All women who gave birth during this period were interviewed on breastfeeding and complementary feeding practices at recruitment and this information was updated twice, at four-monthly intervals. Cox proportional hazard analysis was used to determine factors associated with cessation of breastfeeding in infancy and early introduction of complementary foods. Results There was universal breastfeeding with almost all children (99% having ever been breastfed. However, more than a third (37% were not breastfed in the first hour following delivery, and 40% were given something to drink other than the mothers' breast milk within 3 days after delivery. About 85% of infants were still breastfeeding by the end of the 11th month. Exclusive breastfeeding for the first six months was rare as only about 2% of infants were exclusively breastfed for six months. Factors associated with sub-optimal infant breastfeeding and feeding practices in these settings include child's sex; perceived size at birth; mother's marital status, ethnicity; education level; family planning (pregnancy desirability; health seeking behaviour (place of delivery and; neighbourhood

Maintenance of polygenic sex determination in a fluctuating environment: an individual-based model.

Science.gov (United States)

Bateman, A W; Anholt, B R

2017-05-01

R. A. Fisher predicted that individuals should invest equally in offspring of both sexes, and that the proportion of males and females produced (the primary sex ratio) should evolve towards 1:1 when unconstrained. For many species, sex determination is dependent on sex chromosomes, creating a strong tendency for balanced sex ratios, but in other cases, multiple autosomal genes interact to determine sex. In such cases, the maintenance of multiple sex-determining alleles at multiple loci and the consequent among-family variability in sex ratios presents a puzzle, as theory predicts that such systems should be unstable. Theory also predicts that environmental influences on sex can complicate outcomes of genetic sex determination, and that population structure may play a role. Tigriopus californicus, a copepod that lives in splash-pool metapopulations and exhibits polygenic and environment-dependent sex determination, presents a test case for relevant theory. We use this species as a model for parameterizing an individual-based simulation to investigate conditions that could maintain polygenic sex determination. We find that metapopulation structure can delay the degradation of polygenic sex determination and that periods of alternating frequency-dependent selection, imposed by seasonal fluctuations in environmental conditions, can maintain polygenic sex determination indefinitely. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Sex determination using free fetal DNA in early pregnancy: With the approach to sex linked recessive disorders

Directory of Open Access Journals (Sweden)

Amir Monfaredan

2017-03-01

Full Text Available Introduction: Prenatal diagnosis is testing for detection of diseases or conditions in a fetus or embryo before it is born. Most of prenatal diagnostic (PD techniques are invasive and done in late stages of pregnancy. Using fetal DNA in maternal blood for fetal sex determination in early pregnancy might help in management of X-linked genetic diseases. This study aimed to investigate the accuracy of sex determination using fetal DNA in maternal blood at 8-12 weeks of gestation. Methods: In this cross-sectional study, 30 pregnant women at 8-12 weeks of gestation were enrolled. The sex-determining region Y (SRY gene expression with the internal control (IC glyceraldehyde 3-phosphate dehydrogenase (GAPDH was investigated with quantitative real-time polymerase chain reaction (PCR using specific primers and probes. Results: Accuracy of sex determination with SRY gene expression in 8-12 weeks of pregnancy were 85%, 85%, 90% and 100% respectively. Conclusion: It seems that fetal sex determining using fetal DNA in maternal blood is a reliable method for early stage of pregnancy.

Comparative In silico Study of Sex-Determining Region Y (SRY) Protein Sequences Involved in Sex-Determining.

Science.gov (United States)

Vakili Azghandi, Masoume; Nasiri, Mohammadreza; Shamsa, Ali; Jalali, Mohsen; Shariati, Mohammad Mahdi

2016-04-01

The SRY gene (SRY) provides instructions for making a transcription factor called the sex-determining region Y protein. The sex-determining region Y protein causes a fetus to develop as a male. In this study, SRY of 15 spices included of human, chimpanzee, dog, pig, rat, cattle, buffalo, goat, sheep, horse, zebra, frog, urial, dolphin and killer whale were used for determine of bioinformatic differences. Nucleotide sequences of SRY were retrieved from the NCBI databank. Bioinformatic analysis of SRY is done by CLC Main Workbench version 5.5 and ClustalW (http:/www.ebi.ac.uk/clustalw/) and MEGA6 softwares. The multiple sequence alignment results indicated that SRY protein sequences from Orcinus orca (killer whale) and Tursiopsaduncus (dolphin) have least genetic distance of 0.33 in these 15 species and are 99.67% identical at the amino acid level. Homosapiens and Pantroglodytes (chimpanzee) have the next lowest genetic distance of 1.35 and are 98.65% identical at the amino acid level. These findings indicate that the SRY proteins are conserved in the 15 species, and their evolutionary relationships are similar.

Sex determination: insights from the silkworm

Indian Academy of Sciences (India)

2010-09-06

determination pathway that controls most sex-specific phenotypes, is a .... Sports and Culture, Government of Japan, grant-in-aid for Young. Scientists ... Berghammer A. J., Klingler M. and Wimmer E. A. 1999 A universal marker for ...

Gonadal expression of Sf1 and aromatase during sex determination in the red-eared slider turtle (Trachemys scripta), a reptile with temperature-dependent sex determination.

Science.gov (United States)

Ramsey, Mary; Shoemaker, Christina; Crews, David

2007-12-01

Many egg-laying reptiles have temperature-dependent sex determination (TSD), where the offspring sex is determined by incubation temperature during a temperature-sensitive period (TSP) in the middle third of development. The underlying mechanism transducing a temperature cue into an ovary or testis is unknown, but it is known that steroid hormones play an important role. During the TSP, exogenous application of estrogen can override a temperature cue and produce females, while blocking the activity of aromatase (Cyp19a1), the enzyme that converts testosterone to estradiol, produces males from a female-biased temperature. The production of estrogen is a key step in ovarian differentiation for many vertebrates, including TSD reptiles, and temperature-based differences in aromatase expression during the TSP may be a critical step in ovarian determination. Steroidogenic factor-1 (Sf1) is a key gene in vertebrate sex determination and regulates many steroidogenic enzymes, including aromatase. We find that Sf1 and aromatase are differentially expressed during sex determination in the red-eared slider turtle, Trachemys scripta elegans. Sf1 is expressed at higher levels during testis development while aromatase expression increases during ovary determination. We also assayed Sf1 and aromatase response to sex-reversing treatments via temperature or the modulation of estrogen availability. Sf1 expression was redirected to low-level female-specific patterns with feminizing temperature shift or exogenous estradiol application and redirected to more intense male-specific patterns with male-producing temperature shift or inhibition of aromatase activity. Conversely, aromatase expression was redirected to more intense female-specific patterns with female-producing treatment and redirected toward diffuse low-level male-specific patterns with masculinizing sex reversal. Our data do not lend support to a role for Sf1 in the regulation of aromatase expression during slider turtle sex

Conservation of Sex-Linked Markers among Conspecific Populations of a Viviparous Skink, Niveoscincus ocellatus, Exhibiting Genetic and Temperature-Dependent Sex Determination

Science.gov (United States)

Burridge, Christopher P; Ezaz, Tariq; Wapstra, Erik

2018-01-01

Abstract Sex determination systems are exceptionally diverse and have undergone multiple and independent evolutionary transitions among species, particularly reptiles. However, the mechanisms underlying these transitions have not been established. Here, we tested for differences in sex-linked markers in the only known reptile that is polymorphic for sex determination system, the spotted snow skink, Niveoscincus ocellatus, to quantify the genomic differences that have accompanied this transition. In a highland population, sex is determined genetically, whereas in a lowland population, offspring sex ratio is influenced by temperature. We found a similar number of sex-linked loci in each population, including shared loci, with genotypes consistent with male heterogamety (XY). However, population-specific linkage disequilibrium suggests greater differentiation of sex chromosomes in the highland population. Our results suggest that transitions between sex determination systems can be facilitated by subtle genetic differences. PMID:29659810

How is sex determined in insects?

Indian Academy of Sciences (India)

gan's student Calvin Bridges formulated his classic balance theory of sex determination in ... affect not only specific traits but also the entire sexual fate of an individual. ... the decision whether to become male or female is conveyed very early in ...

Comparative In silico Study of Sex-Determining Region Y (SRY Protein Sequences Involved in Sex-Determining

Directory of Open Access Journals (Sweden)

Masoume Vakili Azghandi

2016-05-01

Full Text Available Background: The SRY gene (SRY provides instructions for making a transcription factor called the sex-determining region Y protein. The sex-determining region Y protein causes a fetus to develop as a male. In this study, SRY of 15 spices included of human, chimpanzee, dog, pig, rat, cattle, buffalo, goat, sheep, horse, zebra, frog, urial, dolphin and killer whale were used for determine of bioinformatic differences. Methods: Nucleotide sequences of SRY were retrieved from the NCBI databank. Bioinformatic analysis of SRY is done by CLC Main Workbench version 5.5 and ClustalW (http:/www.ebi.ac.uk/clustalw/ and MEGA6 softwares. Results: The multiple sequence alignment results indicated that SRY protein sequences from Orcinus orca (killer whale and Tursiopsaduncus (dolphin have least genetic distance of 0.33 in these 15 species and are 99.67% identical at the amino acid level. Homosapiens and Pantroglodytes (chimpanzee have the next lowest genetic distance of 1.35 and are 98.65% identical at the amino acid level. Conclusion: These findings indicate that the SRY proteins are conserved in the 15 species, and their evolutionary relationships are similar.

Sex determination in gibbons of genus Nomascus using non-invasive method

Directory of Open Access Journals (Sweden)

Petra Bolechová

2016-01-01

Full Text Available Gibbons of the genus Nomascus have a strong sexual dimorphism and dichromatism. As they mature, both sexes develop sex-specific pelage colour. In combination with physical similarities in the genitalia with both sexes, there are problems with determining the sex of young individuals compared to other genus of gibbons. This is a pilot study applying a multiplex polymerase chain reactions based on a non-invasive method for sex determination of gibbons. The study was conducted on 22 faecal samples from gibbons of the genus Nomascus. The animals were monitored by staff so that the samples were identified correctly and each sample was collected immediately after the defecation. Results confirmed the sex in all adult and juvenile animals with known sex; and 2 females and 5 males in juveniles were determined with unknown sex. The results of direct examination completely corresponded with the PCR results. The PCR reaction with template DNA isolated from faecal material required BSA usage, however, we observed the occurrence of nonspecific fragments. This did not affect the reliability of our results and we confirmed the usability of this method for this genus.

Determining the attitudes and use of complementary, alternative, and integrative medicine among undergraduates.

Science.gov (United States)

Liu, Michael A; Huynh, Ngoc-Tram; Broukhim, Michael; Cheung, Douglas H; Schuster, Tonya L; Najm, Wadie

2014-09-01

To (1) determine the attitudes, perceptions, and use of complementary, alternative, and integrative medicine among undergraduate students; (2) assess whether these students would benefit from more academic exposure to complementary and alternative medicine (CAM) and promotion of integrative medicine (IM); and (3) gauge the need and desire of undergraduates, particularly pre-health learners, to take courses about CAM/IM. This cross-sectional electronic survey study was conducted on the campus of the University of California (UC) Irvine. Selection criteria included being at least 18 years of age and a current undergraduate at UC Irvine. All survey responses were collected between November 20, 2010, and June 1, 2011. The data were analyzed by using Stata software, version 11-SE (Stata Corp., College Station, TX). Completed surveys were received from 2839 participants (mean age of respondents, 20.2 years). Thirty-five percent had used CAM within the past 12 months, and 92.8% believed CAM to be at least somewhat effective; however, only 31% had prior education on CAM. After adjustment for variables, familiarity and belief in effectiveness were both highly linked to the use of CAM, with ascending odds ratios (ORs; 95% confidence interval [CI]) of 3.9 (3.1-4.9), 8.1 (5.7-11.5), 13.4 (6.0-30.2), 2.1 (1.3-3.4), 4.9 (3.0-7.8), and 12.7 (6.9-23.4) among increasing categories (all p<0.01). Sex (OR, 1.26 [95% CI, 1.01-1.56]; p<0.05), Asian ethnicity (1.46 [1.14-1.88]; p<0.01), and prior education (1.26 [1.01-1.57]; p<0.05) were also significantly correlated to the use of CAM after adjustment. Most respondents indicated that they were likely to take a CAM college course if it fulfilled a graduation requirement (63.6%) or was offered within their major (56.4%). Overall, this large-scale study supports the ideas that education plays a pivotal factor in the decision to use CAM and that there is a large demand for additional CAM knowledge among college students.

Sex determination using the Probabilistic Sex Diagnosis (DSP: Diagnose Sexuelle Probabiliste) tool in a virtual environment.

Science.gov (United States)

Chapman, Tara; Lefevre, Philippe; Semal, Patrick; Moiseev, Fedor; Sholukha, Victor; Louryan, Stéphane; Rooze, Marcel; Van Sint Jan, Serge

2014-01-01

The hip bone is one of the most reliable indicators of sex in the human body due to the fact it is the most dimorphic bone. Probabilistic Sex Diagnosis (DSP: Diagnose Sexuelle Probabiliste) developed by Murail et al., in 2005, is a sex determination method based on a worldwide hip bone metrical database. Sex is determined by comparing specific measurements taken from each specimen using sliding callipers and computing the probability of specimens being female or male. In forensic science it is sometimes not possible to sex a body due to corpse decay or injury. Skeletalization and dissection of a body is a laborious process and desecrates the body. There were two aims to this study. The first aim was to examine the accuracy of the DSP method in comparison with a current visual sexing method on sex determination. A further aim was to see if it was possible to virtually utilise the DSP method on both the hip bone and the pelvic girdle in order to utilise this method for forensic sciences. For the first part of the study, forty-nine dry hip bones of unknown sex were obtained from the Body Donation Programme of the Université Libre de Bruxelles (ULB). A comparison was made between DSP analysis and visual sexing on dry bone by two researchers. CT scans of bones were then analysed to obtain three-dimensional (3D) virtual models and the method of DSP was analysed virtually by importing the models into a customised software programme called lhpFusionBox which was developed at ULB. The software enables DSP distances to be measured via virtually-palpated bony landmarks. There was found to be 100% agreement of sex between the manual and virtual DSP method. The second part of the study aimed to further validate the method by analysing thirty-nine supplementary pelvic girdles of known sex blind. There was found to be a 100% accuracy rate further demonstrating that the virtual DSP method is robust. Statistically significant differences were found in the identification of sex

Identification of the sex-determining locus in grass puffer (Takifugu niphobles) provides evidence for sex-chromosome turnover in a subset of Takifugu species

Science.gov (United States)

Atsumi, Kazufumi; Kamiya, Takashi; Nozawa, Aoi; Aoki, Yuma; Tasumi, Satoshi; Koyama, Takashi; Nakamura, Osamu; Suzuki, Yuzuru

2018-01-01

There is increasing evidence for frequent turnover in sex chromosomes in vertebrates. Yet experimental systems suitable for tracing the detailed process of turnover are rare. In theory, homologous turnover is possible if the new sex-determining locus is established on the existing sex-chromosome. However, there is no empirical evidence for such an event. The genus Takifugu includes fugu (Takifugu rubripes) and its two closely-related species whose sex is most likely determined by a SNP at the Amhr2 locus. In these species, males are heterozygous, with G and C alleles at the SNP site, while females are homozygous for the C allele. To determine if a shift in the sex-determining locus occurred in another member of this genus, we used genetic mapping to characterize the sex-chromosome systems of Takifugu niphobles. We found that the G allele of Amhr2 is absent in T. niphobles. Nevertheless, our initial mapping suggests a linkage between the phenotypic sex and the chromosome 19, which harbors the Amhr2 locus. Subsequent high-resolution analysis using a sex-reversed fish demonstrated that the sex-determining locus maps to the proximal end of chromosome 19, far from the Amhr2 locus. Thus, it is likely that homologous turnover involving these species has occurred. The data also showed that there is a male-specific reduction of recombination around the sex-determining locus. Nevertheless, no evidence for sex-chromosome differentiation was detected: the reduced recombination depended on phenotypic sex rather than genotypic sex; no X- or Y-specific maker was obtained; the YY individual was viable. Furthermore, fine-scale mapping narrowed down the new sex-determining locus to the interval corresponding to approximately 300-kb of sequence in the fugu genome. Thus, T. niphobles is determined to have a young and small sex-determining region that is suitable for studying an early phase of sex-chromosome evolution and the mechanisms underlying turnover of sex chromosome. PMID

Sex and PRNP genotype determination in preimplantation caprine embryos.

Science.gov (United States)

Guignot, F; Perreau, C; Cavarroc, C; Touzé, J-L; Pougnard, J-L; Dupont, F; Beckers, J-F; Rémy, B; Babilliot, J-M; Bed'Hom, B; Lamorinière, J M; Mermillod, P; Baril, G

2011-08-01

The objective of this study was to test the accuracy of genotype diagnosis after whole amplification of DNA extracted from biopsies obtained by trimming goat embryos and to evaluate the viability of biopsied embryos after vitrification/warming and transfer. Whole genome amplification (WGA) was performed using Multiple Displacement Amplification (MDA). Sex and prion protein (PRNP) genotypes were determined. Sex diagnosis was carried out by PCR amplification of ZFX/ZFY and Y chromosome-specific sequences. Prion protein genotype determination was performed on codons 142, 154, 211, 222 and 240. Embryos were collected at day 7 after oestrus and biopsied either immediately after collection (blastocysts and expanded blastocysts) or after 24 h of in vitro culture (compacted morulae). Biopsied embryos were frozen by vitrification. Vitrified whole embryos were kept as control. DNA of biopsies was extracted and amplified using MDA. Sex diagnosis was efficient for 97.4% of biopsies and PRNP genotyping was determined in 78.7% of biopsies. After embryo transfer, no significant difference was observed in kidding rate between biopsied and vitrified control embryos, whereas embryo survival rate was different between biopsied and whole vitrified embryos (p = 0.032). At birth, 100% of diagnosed sex and 98.2% of predetermined codons were correct. Offspring PRNP profiles were in agreement with parental genotype. Whole genome amplification with MDA kit coupled with sex diagnosis and PRNP genotype predetermination are very accurate techniques to genotype goat embryos before transfer. These novel results allow us to plan selection of scrapie-resistant genotypes and kid sex before transfer of cryopreserved embryo. © 2010 Blackwell Verlag GmbH.

Segregating variation for temperature-dependent sex determination in a lizard.

Science.gov (United States)

Rhen, T; Schroeder, A; Sakata, J T; Huang, V; Crews, D

2011-04-01

Temperature-dependent sex determination (TSD) was first reported in 1966 in an African lizard. It has since been shown that TSD occurs in some fish, several lizards, tuataras, numerous turtles and all crocodilians. Extreme temperatures can also cause sex reversal in several amphibians and lizards with genotypic sex determination. Research in TSD species indicates that estrogen signaling is important for ovary development and that orthologs of mammalian genes have a function in gonad differentiation. Nevertheless, the mechanism that actually transduces temperature into a biological signal for ovary versus testis development is not known in any species. Classical genetics could be used to identify the loci underlying TSD, but only if there is segregating variation for TSD. Here, we use the 'animal model' to analyze inheritance of sexual phenotype in a 13-generation pedigree of captive leopard geckos, Eublepharis macularius, a TSD reptile. We directly show genetic variance and genotype-by-temperature interactions for sex determination. Additive genetic variation was significant at a temperature that produces a female-biased sex ratio (30°C), but not at a temperature that produces a male-biased sex ratio (32.5°C). Conversely, dominance variance was significant at the male-biased temperature (32.5°C), but not at the female-biased temperature (30°C). Non-genetic maternal effects on sex determination were negligible in comparison with additive genetic variance, dominance variance and the primary effect of temperature. These data show for the first time that there is segregating variation for TSD in a reptile and consequently that a quantitative trait locus analysis would be practicable for identifying the genes underlying TSD.

Guardian small RNAs and sex determination.

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Katsuma, Susumu; Kawamoto, Munetaka; Kiuchi, Takashi

2014-01-01

The W chromosome of the silkworm Bombyx mori has been known to determine femaleness for more than 80 years. However, the feminizing gene has not been molecularly identified, because the B. mori W chromosome is almost fully occupied by a large number of transposable elements. The W chromosome-derived feminizing factor of B. mori was recently shown to be a female-specific PIWI-interacting RNA (piRNA). piRNAs are small RNAs that potentially repress invading "non-self" elements (e.g., transposons and virus-like elements) by associating with PIWI proteins. Our results revealed that female-specific piRNA precursors, which we named Fem, are transcribed from the sex-determining region of the W chromosome at the early embryonic stage and are processed into a single mature piRNA (Fem piRNA). Fem piRNA forms a complex with Siwi (silkworm Piwi), which cleaves a protein-coding mRNA transcribed from the Z chromosome. RNA interference of this Z-linked gene, which we named Masc, revealed that this gene encodes a protein required for masculinization and dosage compensation. Fem and Masc both participate in the ping-pong cycle of the piRNA amplification loop by associating with the 2 B. mori PIWI proteins Siwi and BmAgo3 (silkworm Ago3), respectively, indicating that the piRNA-mediated interaction between the 2 sex chromosomes is the primary signal for the B. mori sex determination cascade. Fem is a non-transposable repetitive sequence on the W chromosome, whereas Masc is a single-copy protein-coding gene. It is of great interest how the piRNA system recognizes "self "Masc mRNA as "non-self" RNA.

Pulp tissue in sex determination: A fluorescent microscopic study

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Nayar, Amit; Singh, Harkanwal Preet; Leekha, Swati

2014-01-01

Aims: To determine and compare the reliability of pulp tissue in determination of sex and to analyze whether caries have any effect on fluorescent body test. Materials and Methods: This study was carried on 50 maxillary and mandibular teeth (25 male teeth and 25 female teeth), which were indicated for extraction. The teeth are categorized into 5 groups, 10 each (5 from males and 5 from females) on the basis of caries progression. The pulp cells are stained with quinacrine hydrochloride and observed with fluorescent microscope for fluorescent body. Gender is determined by identification of Y chromosome fluorescence in dental pulp. Results: Fluorescent bodies were found to be more in sound teeth in males as the caries increase the mean percentage of fluorescent bodies observed decreases in males. We also observed the fluorescent spots in females, and the value of the spot increases in female as the caries progresses, thereby giving false positive results in females. Conclusion: Sex determination by fluorescent staining of the Y chromosome is a reliable technique in teeth with healthy pulps or caries with enamel or up to half way of dentin. Teeth with caries involving pulp cannot be used for sex determination. PMID:25125912

Karyotype analysis and sex determination in Australian Brush-turkeys (Alectura lathami.

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Madison T Ortega

Full Text Available Sexual differentiation across taxa may be due to genetic sex determination (GSD and/or temperature sex determination (TSD. In many mammals, males are heterogametic (XY; whereas females are homogametic (XX. In most birds, the opposite is the case with females being heterogametic (ZW and males the homogametic sex (ZZ. Many reptile species lack sex chromosomes, and instead, sexual differentiation is influenced by temperature with specific temperatures promoting males or females varying across species possessing this form of sexual differentiation, although TSD has recently been shown to override GSD in Australian central beaded dragons (Pogona vitticeps. There has been speculation that Australian Brush-turkeys (Alectura lathami exhibit TSD alone and/or in combination with GSD. Thus, we sought to determine if this species possesses sex chromosomes. Blood was collected from one sexually mature female and two sexually mature males residing at Sylvan Heights Bird Park (SHBP and shipped for karyotype analysis. Karyotype analysis revealed that contrary to speculation, Australian Brush-turkeys possess the classic avian ZW/ZZ sex chromosomes. It remains a possibility that a biased primary sex ratio of Australian Brush-turkeys might be influenced by maternal condition prior to ovulation that result in her laying predominantly Z- or W-bearing eggs and/or sex-biased mortality due to higher sensitivity of one sex in environmental conditions. A better understanding of how maternal and extrinsic factors might differentially modulate ovulation of Z- or W-bearing eggs and hatching of developing chicks possessing ZW or ZZ sex chromosomes could be essential in conservation strategies used to save endangered members of Megapodiidae.

[Breastfeeding, complementary feeding and risk of childhood obesity].

Science.gov (United States)

Sandoval Jurado, Luis; Jiménez Báez, María Valeria; Olivares Juárez, Sibli; de la Cruz Olvera, Tomas

2016-11-01

To evaluate the pattern of breastfeeding and weaning as a risk of obesity in pre-school children from a Primary Care Unit. Cross-sectional analytical study LOCATION: Cancun, Quintana Roo (Mexico). Children from 2-4 years of age from a Primary Care Unit. Duration of total and exclusive breastfeeding, age and food utilized for complementary feeding reported by the mother or career of the child and nutritional status assessment evaluated by body mass index (BMI) ≥ 95 percentile. Determination of prevalence ratio (PR), odds ratio (OR), chi squared (x2), and binary logistic regression. The study included 116 children (55.2% girls) with a mean age of 3.2 years, with obesity present in 62.1%, Exclusive breastfeeding in 72.4% with mean duration of 2.3 months, and age at introducing solids foods was 5.0 months. There was a difference for breastfeeding and complementary feeding by gender sex (P<.05). A PR=3.9 (95% CI: 1.49-6.34) was calculated for exclusive breastfeeding and risk of obesity. The model showed no association between these variables and obesity in children CONCLUSIONS: Exclusive breastfeeding of less than three months is associated with almost 4 more times in obese children. There was a difference in age of complementary feeding, duration of breastfeeding, and formula milk consumption time for obese and non-obese children. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Sexy splicing: regulatory interplays governing sex determination from Drosophila to mammals.

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Lalli, Enzo; Ohe, Kenji; Latorre, Elisa; Bianchi, Marco E; Sassone-Corsi, Paolo

2003-02-01

A remarkable array of strategies is used to produce sexual differentiation in different species. Complex gene hierarchies govern sex determination pathways, as exemplified by the classic D. melanogaster paradigm, where an interplay of transcriptional, splicing and translational mechanisms operate. Molecular studies support the hypothesis that genetic sex determination pathways evolved in reverse order, from downstream to upstream genes, in the cascade. The recent identification of a role for the key regulatory factors SRY and WT1(+KTS) in pre-mRNA splicing indicates that important steps in the mammalian sex determination process are likely to operate at the post-transcriptional level.

Some progress in sexual reproduction and sex determination of ...

African Journals Online (AJOL)

As a result of this, elucidating the basic physiological mechanisms of algae becomes even more urgent. Of all the fields, sexual reproduction and sex determination are basic and essential aspects. In this review, we summarized the advances of sex in several typical algae which are of great economic importance and often ...

Sex determination: ways to evolve a hermaphrodite.

OpenAIRE

Braendle , Christian; Félix , Marie-Anne

2006-01-01

Most species of the nematode genus Caenorhabditis reproduce through males and females; C. elegans and C. briggsae, however, produce self-fertile hermaphrodites instead of females. These transitions to hermaphroditism evolved convergently through distinct modifications of germline sex determination mechanisms.

MORPHOMETRIC EVALUATION OF FORAMEN MAGNUM FOR SEX DETERMINATION IN A DOCUMENTED NORTH INDIAN SAMPLE

OpenAIRE

Jain; Alok Kumar; Pankaj

2013-01-01

ABSTRACT: Sex determination is used in anthropology, forensic medicine and medic o - legal cases. It is (1) remarked that “next to the pelvis, the skull is the most easily sexed portion of the skeleton”. It has been suggested (2 - 5) that the measurements of the foramen magnum are useful for determining the sex. There are two osteological techniques used to determine the sex of an individual; the first is visual assessment to evaluate the morphological sex tra...

Efficacy of cheiloscopy in determination of sex among South indians.

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Kautilya D, Vijay; Bodkha, Pravir; Rajamohan, Naveen

2013-10-01

Human identification plays a vital role in any crime investigation. Along with the various other established methods, cheiloscopy also plays a key role in linking the criminal with the crime. The ability of a technique in differentiating the sex of a person in the field can help in screening a large number of suspects. This study evaluated the efficacy of cheiloscopy in determination of sex among South Indians. It also studied the pattern of dimorphism in the lips and lip prints of south Indians. Lip prints from 100 medical students (50 males and 50 females) were obtained and were analyzed, based on Tsuchihashi and Suzuki classification, to check for dimorphism. Lip dimensions were studied by using standard sliding calipers for dimorphism. The most common pattern of lip print among males was Type III as compared to Type I in females. The outer four portions of the lip showed statistically significant differences in males and females. Middle portion of the lip was statistically insignificant in sex determination, based on lip print patterns. Thickness of the lip was significantly larger in males as compared to that in females and this criterion could be used to establish a logistic regression for determination of sex of a person. Lips not only significantly differ among the males and females in the pattern of the lip print that they present, but they also differ in their size. These features can effectively be used to determine the sex of a person accurately.

Direct LAMP Assay without Prior DNA Purification for Sex Determination of Papaya

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Chi-Chu Tsai

2016-09-01

Full Text Available Papaya (Carica papaya L. is an economically important tropical fruit tree with hermaphrodite, male and female sex types. Hermaphroditic plants are the major type used for papaya production because their fruits have more commercial advantages than those of female plants. Sex determination of the seedlings, or during the early growth stages, is very important for the papaya seedling industry. Thus far, the only method for determining the sex type of a papaya at the seedling stage has been DNA analysis. In this study, a molecular technique—based on DNA analysis—was developed for detecting male-hermaphrodite-specific markers to examine the papaya’s sex type. This method is based on the loop-mediated isothermal amplification (LAMP and does not require prior DNA purification. The results show that the method is an easy, efficient, and inexpensive way to determine a papaya’s sex. This is the first report on the LAMP assay, using intact plant materials-without DNA purification-as samples for the analysis of sex determination of papaya. We found that using high-efficiency DNA polymerase was essential for successful DNA amplification, using trace intact plant material as a template DNA source.

Sex determination in Madagascar geckos of the genus Paroedura (Squamata: Gekkonidae): are differentiated sex chromosomes indeed so evolutionary stable?

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Koubová, Martina; Johnson Pokorná, Martina; Rovatsos, Michail; Farkačová, Klára; Altmanová, Marie; Kratochvíl, Lukáš

2014-12-01

Among amniote vertebrates, geckos represent a clade with exceptional variability in sex determination; however, only a minority of species of this highly diverse group has been studied in this respect. Here, we describe for the first time a female heterogamety in the genus Paroedura, the group radiated in Madagascar and adjacent islands. We identified homomorphic ZZ/ZW sex chromosomes with a highly heterochromatic W chromosome in Paroedura masobe, Paroedura oviceps, Paroedura karstophila, Paroedura stumpffi, and Paroedura lohatsara. Comparative genomic hybridization (CGH) revealed that female-specific sequences are greatly amplified in the W chromosome of P. lohatsara and that P. gracilis seems to possess a derived system of multiple sex chromosomes. Contrastingly, neither CGH nor heterochromatin visualization revealed differentiated sex chromosomes in the members of the Paroedura picta-Paroedura bastardi-Paroedura ibityensis clade, which is phylogenetically nested within lineages with a heterochromatic W chromosome. As a sex ratio consistent with genotypic sex determination has been reported in P. picta, it appears that the members of the P. picta-P. bastardi-P. ibityensis clade possess homomorphic, poorly differentiated sex chromosomes and may represent a rare example of evolutionary loss of highly differentiated sex chromosomes. Fluorescent in situ hybridization (FISH) with a telomeric probe revealed a telomere-typical pattern in all species and an accumulation of telomeric sequences in the centromeric region of autosomes in P. stumpffi and P. bastardi. Our study adds important information for the greater understanding of the variability and evolution of sex determination in geckos and demonstrates how the geckos of the genus Paroedura provide an interesting model for studying the evolution of the sex chromosomes.

Sex Determination by Morphometry of Lips

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B. Senthil Kumar

2018-04-01

Full Text Available Background: Facial anthropometric parameters are affected by various factors including age, sex, ethnicity, socioeconomic status, environment and region. The lips become thinner as age increases and the wet line moves caudally, in addition oral commissure begins to downturn. Aim and Objectives: The purpose of this study was to create a baseline data in determining the sex of the people from India and Malaysia depending on morphometry of lips. Materials and Methods:Atotal of 100 Malaysians and 100 South Indians were enrolled for the study. Various morphometric measurements of lips were taken using Vernier caliper. The data were analyzed by one way ANOVAto find out the significance among the sex and population. Results: All the measurements of upper and lower lips were higher in males as compared to females and thus sexual dimorphism exists. Mouth width and height were found to be more in Indian males followed by Malaysian males whereas in females it's vice versa. Vermilion upper lip occupied less than half of total upper lip height, whereas vermilion lower lip occupied more than half of total lower lip height in both the population. Indian males and females differed significantly in lip parameters from those of Malaysian males and females. Conclusion: It can be concluded from the study that same standards cannot be used on each other's populations for identification and cosmetic surgery. The study highlights the applied significance of observations to forensic medicine namely, personal identification, racial and sex dimorphic criteria of identification.

Sex determination strategies in 2012: towards a common regulatory model?

Science.gov (United States)

2012-01-01

Sex determination is a complicated process involving large-scale modifications in gene expression affecting virtually every tissue in the body. Although the evolutionary origin of sex remains controversial, there is little doubt that it has developed as a process of optimizing metabolic control, as well as developmental and reproductive functions within a given setting of limited resources and environmental pressure. Evidence from various model organisms supports the view that sex determination may occur as a result of direct environmental induction or genetic regulation. The first process has been well documented in reptiles and fish, while the second is the classic case for avian species and mammals. Both of the latter have developed a variety of sex-specific/sex-related genes, which ultimately form a complete chromosome pair (sex chromosomes/gonosomes). Interestingly, combinations of environmental and genetic mechanisms have been described among different classes of animals, thus rendering the possibility of a unidirectional continuous evolutionary process from the one type of mechanism to the other unlikely. On the other hand, common elements appear throughout the animal kingdom, with regard to a) conserved key genes and b) a central role of sex steroid control as a prerequisite for ultimately normal sex differentiation. Studies in invertebrates also indicate a role of epigenetic chromatin modification, particularly with regard to alternative splicing options. This review summarizes current evidence from research in this hot field and signifies the need for further study of both normal hormonal regulators of sexual phenotype and patterns of environmental disruption. PMID:22357269

Sex-specific determinants of fitness in a social mammal.

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Lardy, Sophie; Allainé, Dominique; Bonenfant, Christophe; Cohas, Aurélie

2015-11-01

Sociality should evolve when the fitness benefits of group living outweigh the costs. Theoretical models predict an optimal group size maximizing individual fitness. However, beyond the number of individuals present in a group, the characteristics of these individuals, like their sex, are likely to affect the fitness payoffs of group living. Using 20 years of individually based data on a social mammal, the Alpine marmot (Marmota marmota), we tested for the occurrence of an optimal group size and composition, and for sex-specific effects of group characteristics on fitness. Based on lifetime data of 52 males and 39 females, our findings support the existence of an optimal group size maximizing male fitness and an optimal group composition maximizing fitness of males and females. Additionally, although group characteristics (i.e., size, composition and instability) affecting male and female fitness differed, fitness depended strongly on the number of same-sex subordinates within the social group in the two sexes. By comparing multiple measures of social group characteristics and of fitness in both sexes, we highlighted the sex-specific determinants of fitness in the two sexes and revealed the crucial role of intrasexual competition in shaping social group composition.

Insect Sex Determination Manipulated by Their Endosymbionts: Incidences, Mechanisms and Implications.

Science.gov (United States)

Kageyama, Daisuke; Narita, Satoko; Watanabe, Masaya

2012-02-10

The sex-determining systems of arthropods are surprisingly diverse. Some species have male or female heterogametic sex chromosomes while other species do not have sex chromosomes. Most species are diploids but some species, including wasps, ants, thrips and mites, are haplodiploids (n in males; 2n in females). Many of the sexual aberrations, such as sexual mosaics, sex-specific lethality and conversion of sexuality, can be explained by developmental defects including double fertilization of a binucleate egg, loss of a sex chromosome or perturbation of sex-determining gene expression, which occur accidentally or are induced by certain environmental conditions. However, recent studies have revealed that such sexual aberrations can be caused by various groups of vertically-transmitted endosymbiotic microbes such as bacteria of the genera Wolbachia, Rickettsia, Arsenophonus, Spiroplasma and Cardinium, as well as microsporidian protists. In this review, we first summarize the accumulated data on endosymbiont-induced sexual aberrations, and then discuss how such endosymbionts affect the developmental system of their hosts and what kinds of ecological and evolutionary effects these endosymbionts have on their host populations.

Similar but not the same: insights into the evolutionary history of paralogous sex-determining genes of the dwarf honey bee Apis florea.

Science.gov (United States)

Biewer, M; Lechner, S; Hasselmann, M

2016-01-01

Studying the fate of duplicated genes provides informative insight into the evolutionary plasticity of biological pathways to which they belong. In the paralogous sex-determining genes complementary sex determiner (csd) and feminizer (fem) of honey bee species (genus Apis), only heterozygous csd initiates female development. Here, the full-length coding sequences of the genes csd and fem of the phylogenetically basal dwarf honey bee Apis florea are characterized. Compared with other Apis species, remarkable evolutionary changes in the formation and localization of a protein-interacting (coiled-coil) motif and in the amino acids coding for the csd characteristic hypervariable region (HVR) are observed. Furthermore, functionally different csd alleles were isolated as genomic fragments from a random population sample. In the predicted potential specifying domain (PSD), a high ratio of πN/πS=1.6 indicated positive selection, whereas signs of balancing selection, commonly found in other Apis species, are missing. Low nucleotide diversity on synonymous and genome-wide, non-coding sites as well as site frequency analyses indicated a strong impact of genetic drift in A. florea, likely linked to its biology. Along the evolutionary trajectory of ~30 million years of csd evolution, episodic diversifying selection seems to have acted differently among distinct Apis branches. Consistently low amino-acid differences within the PSD among pairs of functional heterozygous csd alleles indicate that the HVR is the most important region for determining allele specificity. We propose that in the early history of the lineage-specific fem duplication giving rise to csd in Apis, A. florea csd stands as a remarkable example for the plasticity of initial sex-determining signals.

Mapping of five candidate sex-determining loci in rainbow trout (Oncorhynchus mykiss

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Drew Robert E

2009-01-01

Full Text Available Abstract Background Rainbow trout have an XX/XY genetic mechanism of sex determination where males are the heterogametic sex. The homology of the sex-determining gene (SDG in medaka to Dmrt1 suggested that SDGs evolve from downstream genes by gene duplication. Orthologous sequences of the major genes of the mammalian sex determination pathway have been reported in the rainbow trout but the map position for the majority of these genes has not been assigned. Results Five loci of four candidate genes (Amh, Dax1, Dmrt1 and Sox6 were tested for linkage to the Y chromosome of rainbow trout. We exclude the role of all these loci as candidates for the primary SDG in this species. Sox6i and Sox6ii, duplicated copies of Sox6, mapped to homeologous linkage groups 10 and 18 respectively. Genotyping fishes of the OSU × Arlee mapping family for Sox6i and Sox6ii alleles indicated that Sox6i locus might be deleted in the Arlee lineage. Conclusion Additional candidate genes should be tested for their linkage to the Y chromosome. Mapping data of duplicated Sox6 loci supports previously suggested homeology between linkage groups 10 and 18. Enrichment of the rainbow trout genomic map with known gene markers allows map comparisons with other salmonids. Mapping of candidate sex-determining loci is important for analyses of potential autosomal modifiers of sex-determination in rainbow trout.

The evolution of environmental and genetic sex determination in fluctuating environments.

Science.gov (United States)

Van Dooren, Tom J M; Leimar, Olof

2003-12-01

Twenty years ago, Bulmer and Bull suggested that disruptive selection, produced by environmental fluctuations, can result in an evolutionary transition from environmental sex determination (ESD) to genetic sex determination (GSD). We investigated the feasibility of such a process, using mutation-limited adaptive dynamics and individual-based computer simulations. Our model describes the evolution of a reaction norm for sex determination in a metapopulation setting with partial migration and variation in an environmental variable both within and between local patches. The reaction norm represents the probability of becoming a female as a function of environmental state and was modeled as a sigmoid function with two parameters, one giving the location (i.e., the value of the environmental variable for which an individual has equal chance of becoming either sex) and the other giving the slope of the reaction norm for that environment. The slope can be interpreted as being set by the level of developmental noise in morph determination, with less noise giving a steeper slope and a more switchlike reaction norm. We found convergence stable reaction norms with intermediate to large amounts of developmental noise for conditions characterized by low migration rates, small differential competitive advantages between the sexes over environments, and little variation between individual environments within patches compared to variation between patches. We also considered reaction norms with the slope parameter constrained to a high value, corresponding to little developmental noise. For these we found evolutionary branching in the location parameter and a transition from ESD toward GSD, analogous to the original analysis by Bulmer and Bull. Further evolutionary change, including dominance evolution, produced a polymorphism acting as a GSD system with heterogamety. Our results point to the role of developmental noise in the evolution of sex determination.

Gender/Sex as a Social Determinant of Cardiovascular Risk.

Science.gov (United States)

O'Neil, Adrienne; Scovelle, Anna J; Milner, Allison J; Kavanagh, Anne

2018-02-20

The social gradient for cardiovascular disease (CVD) onset and outcomes is well established. The American Heart Association's Social Determinants of Risk and Outcomes of Cardiovascular Disease Scientific Statement advocates looking beyond breakthroughs in biological science toward a social determinants approach that focuses on socioeconomic position, race and ethnicity, social support, culture and access to medical care, and residential environments to curb the burden of CVD going forward. Indeed, the benefits of this approach are likely to be far reaching, enhancing the positive effects of advances in CVD related to prevention and treatment while reducing health inequities that contribute to CVD onset and outcomes. It is disappointing that the role of gender has been largely neglected despite being a critical determinant of cardiovascular health. It is clear that trajectories and outcomes of CVD differ by biological sex, yet the tendency for sex and gender to be conflated has contributed to the idea that both are constant or fixed with little room for intervention. Rather, as distinct from biological sex, gender is socially produced. Overlaid on biological sex, gender is a broad term that shapes and interacts with one's cognition to guide norms, roles, behaviors, and social relations. It is a fluid construct that varies across time, place, and life stage. Gender can interact with biological sex and, indeed, other social determinants, such as ethnicity and socioeconomic position, to shape cardiovascular health from conception, through early life when health behaviors and risk factors are shaped, into adolescence and adulthood. This article will illustrate how gender shapes the early adoption of health behaviors in childhood, adolescence, and young adulthood by focusing on physical activity, drinking, and smoking behaviors (including the influence of role modeling). We will also discuss the role of gender in psychosocial stress with a focus on trauma from life

Sex Determination of Japanese Quails (Coturnix Coturnix Japonica using with Zoometric Measurements

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Tülin Çiçek Rathert

2017-09-01

Full Text Available The difficulty of sex determination in most poultry species causes significant financial losses for poultry production as birds cannot be separated at early stages of growth for meat or egg production. Therefore it is important to determine bird’s sex with zoometric parameters. This study was carried out to determine the sex of Japanese quails with zoometric measurements, such as live weight, body length, chest depth and chest width. Eighty-eight male and female Japanese quail chicks were used individually for live weight, chest depth (mm, chest width (mm and body length (mm with using digital scaled balance and caliper for every week over a period of six weeks. The weekly collected data were applied to t test for estimating the sex discrimination. The Pearson’s correlation was applied for examining the interrelationship between sex and biometric traits. The results indicated that there was a significant positive correlation between live weight and body length beginning with the 2nd week. Therefore, zoometric measurement of these body traits is suitable for discriminating the sex of Japanese quails in early phase of life.

Heritable Variation for Sex Ratio under Environmental Sex Determination in the Common Snapping Turtle (Chelydra Serpentina)

Science.gov (United States)

Janzen, F. J.

1992-01-01

The magnitude of quantitative genetic variation for primary sex ratio was measured in families extracted from a natural population of the common snapping turtle (Chelydra serpentina), which possesses temperature-dependent sex determination (TSD). Eggs were incubated at three temperatures that produced mixed sex ratios. This experimental design provided estimates of the heritability of sex ratio in multiple environments and a test of the hypothesis that genotype X environment (G X E) interactions may be maintaining genetic variation for sex ratio in this population of C. serpentina. Substantial quantitative genetic variation for primary sex ratio was detected in all experimental treatments. These results in conjunction with the occurrence of TSD in this species provide support for three critical assumptions of Fisher's theory for the microevolution of sex ratio. There were statistically significant effects of family and incubation temperature on sex ratio, but no significant interaction was observed. Estimates of the genetic correlations of sex ratio across environments were highly positive and essentially indistinguishable from +1. These latter two findings suggest that G X E interaction is not the mechanism maintaining genetic variation for sex ratio in this system. Finally, although substantial heritable variation exists for primary sex ratio of C. serpentina under constant temperatures, estimates of the effective heritability of primary sex ratio in nature are approximately an order of magnitude smaller. Small effective heritability and a long generation time in C. serpentina imply that evolution of sex ratios would be slow even in response to strong selection by, among other potential agents, any rapid and/or substantial shifts in local temperatures, including those produced by changes in the global climate. PMID:1592234

Identification of Sex-determining Loci in Pacific White Shrimp Litopeneaus vannamei Using Linkage and Association Analysis.

Science.gov (United States)

Yu, Yang; Zhang, Xiaojun; Yuan, Jianbo; Wang, Quanchao; Li, Shihao; Huang, Hao; Li, Fuhua; Xiang, Jianhai

2017-06-01

The Pacific white shrimp Litopenaeus vannamei is a predominant aquaculture shrimp species in the world. Like other animals, the L. vannamei exhibited sexual dimorphism in growth trait. Mapping of the sex-determining locus will be very helpful to clarify the sex determination system and further benefit the shrimp aquaculture industry towards the production of mono-sex stocks. Based on the data used for high-density linkage map construction, linkage-mapping analysis was conducted. The sex determination region was mapped in linkage group (LG) 18. A large region from 0 to 21.205 cM in LG18 showed significant association with sex. However, none of the markers in this region showed complete association with sex in the other populations. So an association analysis was designed using the female parent, pool of female progenies, male parent, and pool of male progenies. Markers were de novo developed and those showing significant differences between female and male pools were identified. Among them, three sex-associated markers including one fully associated marker were identified. Integration of linkage and association analysis showed that the sex determination region was fine-mapped in a small region along LG18. The identified sex-associated marker can be used for the sex detection of this species at genetic level. The fine-mapped sex-determining region will contribute to the mapping of sex-determining gene and help to clarify sex determination system for L. vannamei.

Sex determination based on a thoracic vertebra and ribs evaluation using clinical chest radiography.

Science.gov (United States)

Tsubaki, Shun; Morishita, Junji; Usumoto, Yosuke; Sakaguchi, Kyoko; Matsunobu, Yusuke; Kawazoe, Yusuke; Okumura, Miki; Ikeda, Noriaki

2017-07-01

Our aim was to investigate whether sex can be determined from a combination of geometric features obtained from the 10th thoracic vertebra, 6th rib, and 7th rib. Six hundred chest radiographs (300 males and 300 females) were randomly selected to include patients of six age groups (20s, 30s, 40s, 50s, 60s, and 70s). Each group included 100 images (50 males and 50 females). A total of 14 features, including 7 lengths, 5 indices for the vertebra, and 2 types of widths for ribs, were utilized and analyzed for sex determination. Dominant features contributing to sex determination were selected by stepwise discriminant analysis after checking the variance inflation factors for multicollinearity. The accuracy of sex determination using a combination of the vertebra and ribs was evaluated from the selected features by the stepwise discriminant analysis. The accuracies in each age group were also evaluated in this study. The accuracy of sex determination based on a combination of features of the vertebra and ribs was 88.8% (533/600). This performance was superior to that of the vertebra or ribs only. Moreover, sex determination of subjects in their 20s demonstrated the highest accuracy (96.0%, 96/100). The features selected in the stepwise discriminant analysis included some features in both the vertebra and ribs. These results indicate the usefulness of combined information obtained from the vertebra and ribs for sex determination. We conclude that a combination of geometric characteristics obtained from the vertebra and ribs could be useful for determining sex. Copyright © 2017 Elsevier B.V. All rights reserved.

How is sex determined in insects? An epilogue

Indian Academy of Sciences (India)

transcriptional factors, which bring about sexual dimorphism in adult flies. ... sex determination, in response to both internal and external selection forces. ... such as in the control of pests (e.g. C. capitata) and vectors of human diseases.

Convergent evolution of chromosomal sex-determining regions in the animal and fungal kingdoms.

Directory of Open Access Journals (Sweden)

James A Fraser

2004-12-01

Full Text Available Sexual identity is governed by sex chromosomes in plants and animals, and by mating type (MAT loci in fungi. Comparative analysis of the MAT locus from a species cluster of the human fungal pathogen Cryptococcus revealed sequential evolutionary events that fashioned this large, highly unusual region. We hypothesize that MAT evolved via four main steps, beginning with acquisition of genes into two unlinked sex-determining regions, forming independent gene clusters that then fused via chromosomal translocation. A transitional tripolar intermediate state then converted to a bipolar system via gene conversion or recombination between the linked and unlinked sex-determining regions. MAT was subsequently subjected to intra- and interallelic gene conversion and inversions that suppress recombination. These events resemble those that shaped mammalian sex chromosomes, illustrating convergent evolution in sex-determining structures in the animal and fungal kingdoms.

Sex determination of Pohnpei Micronesian kingfishers using morphological and molecular genetic techniques

Science.gov (United States)

Kesler, Dylan C.; Lopes, I.F.; Haig, Susan M.

2006-01-01

Conservation-oriented studies of Micronesian Kingfishers (Todiramphus cinnamominus) have been hindered by a lack of basic natural history information, despite the status of the Guam subspecies (T. c. cinnamominus) as one of the most endangered species in the world. We used tissue samples and morphometric measures from museum specimens and wild-captured Pohnpei Micronesian Kingfishers (T. c. reichenbachii) to develop methods for sex determination. We present a modified molecular protocol and a discriminant function that yields the probability that a particular individual is male or female. Our results revealed that females were significantly larger than males, and the discriminant function correctly predicted sex in 73% (30/41) of the individuals. The sex of 86% (18/21) of individuals was correctly assigned when a moderate reliability threshold was set. Sex determination using molecular genetic techniques was more reliable than methods based on morphology. Our results will facilitate recovery efforts for the critically endangered Guam Micronesian Kingfisher and provide a basis for sex determination in the 11 other endangered congeners in the Pacific Basin.

Genetic sex determination in Astatotilapia calliptera, a prototype species for the Lake Malawi cichlid radiation

Science.gov (United States)

Peterson, Erin N.; Cline, Maggie E.; Moore, Emily C.; Roberts, Natalie B.; Roberts, Reade B.

2017-06-01

East African cichlids display extensive variation in sex determination systems. The species Astatotilapia calliptera is one of the few cichlids that reside both in Lake Malawi and in surrounding waterways. A. calliptera is of interest in evolutionary studies as a putative immediate outgroup species for the Lake Malawi species flock and possibly as a prototype ancestor-like species for the radiation. Here, we use linkage mapping to test association of sex in A. calliptera with loci that have been previously associated with genetic sex determination in East African cichlid species. We identify a male heterogametic XY system segregating at linkage group (LG) 7 in an A. calliptera line that originated from Lake Malawi, at a locus previously shown to act as an XY sex determination system in multiple species of Lake Malawi cichlids. Significant association of genetic markers and sex produce a broad genetic interval of approximately 26 megabases (Mb) using the Nile tilapia genome to orient markers; however, we note that the marker with the strongest association with sex is near a gene that acts as a master sex determiner in other fish species. We demonstrate that alleles of the marker are perfectly associated with sex in Metriaclima mbenjii, a species from the rock-dwelling clade of Lake Malawi. While we do not rule out the possibility of other sex determination loci in A. calliptera, this study provides a foundation for fine mapping of the cichlid sex determination gene on LG7 and evolutionary context regarding the origin and persistence of the LG7 XY across diverse, rapidly evolving lineages.

Validation and use of DNA markers for sex determination in papaya (Carica papaya)

International Nuclear Information System (INIS)

Ejaz, M.; Iqbal, M.; Ahmed, I.

2015-01-01

Profitable papaya production requires female and hermaphrodite plants in higher number than male plants. This is only possible if sex of plants is determined at an early growth stage. The present study was conducted to validate sex-linked DNA markers using plants from two Pakistani papaya varieties and subsequently utilize them for determination of sex in juvenile papaya plants. One hundred and five plants (including 49 male and 56 female) of two Pakistani Papaya varieties at flowering stage were screened with six DNA markers viz., W-11, T12, SDP, Napf-76Napf-76, PKBT4 and PKBT5. All male plants exhibited amplification of sex-linked alleles with markers T12 and W11, whereas, 96% and 95% of female plants showed the absence of sex-linked allele with these markers, respectively. Markers SDP, PKBT5 and Napf-76 showed the presence of sex-linked alleles in 98%, 96% and 93% of male plants, respectively, whereas the same markers showed the absence of sex-linked alleles in 100%, 96% and 94% of female plants. One marker, PKBT4 could not produce expected PCR amplification reported previously. The five DNA markers were further used to screen 171 papaya seedlings. These markers clearly differentiated male and female sex types in the studied papaya plants. Results of our study are likely to facilitate Pakistani papaya breeders and growers to incorporate DNA based screening at juvenile stage to determine sex at early stage and to ensure profitable papaya production. (author)

Complementary feeding practices and nutritional status of children 6 ...

African Journals Online (AJOL)

Objectives: Inappropriate complementary feeding practices among children aged 6-23 months is major cause of under nutrition. There is scarce information on the relationship between complementary feeding practices and nutritional status. This study aimed to determine the factors contributing to the complementary ...

Physical Attractiveness, Age, and Sex as Determinants of Reactions to Resumes.

Science.gov (United States)

Quereshi, M. Y.; Kay, Janet P.

1986-01-01

Physical attractiveness, age, and sex were manipulated to determine their effect on the evaluation of 54 hypothetical applicants' resumes for three different jobs by 60 Master's in Business Administration students. Physical attractiveness favorably influenced the suitability ratings for all jobs; raters' sex and age were not significant but…

The sex and sex determination in Pyropia haitanensis (Bangiales, Rhodophyta).

Science.gov (United States)

Zhang, Yuan; Yan, Xing-hong; Aruga, Yusho

2013-01-01

Pyropia haitanensis has a biphasic life cycle with macroscopic gametophytic blade (n) and microscopic filamentous conchocelis (2n) phase. Its gametophytic blades have long been believed to be mainly dioecious. However, when crossing the red mutant (R, ♀) with the wild type (W, ♂), the parental colors were segregated in F1 blades, of which 96.1% were linearly sectored with 2-4 color sectors. When color sectors were excised from the color-sectored blades and cultured singly, 99.7% of the color sectors appeared to be unisexual with an equal sex ratio. Although the sex of color sector did not genetically link with its color, the boundaries of both sex and color sectors coincided precisely. About 87.9% of the examined color-sectored blades were monoecious and the percentage increased with the number of color sectors of a blade. The gametophytic blades from each conchocelis strain produced by parthenogenesis of the excised color sectors were unisexual and unicolor, showing the same sex and color as their original sectors. These results indicate that most of the sexually reproduced Py. haitanensis blades are monoecious, and their sex is controlled by segregation of a pair of alleles during meiosis of conchospore, forming a sex-sectored tetrad. During the subsequent development of blades, one or two lower cell(s) of the tetrad contribute mainly to rhizoid formation, and rarely show their sexual phenotype, leading to reduced frequency of full sex phenotype of the meiotic blades. Moreover, the aberrant segregations of sex genes or color genes in a few of F1 blades were probably due to gene conversions, but there was no sex transfer in Py. haitanensis.

Determinants of use of care provided by complementary and alternative health care practitioners to pregnant women in primary midwifery care : A prospective cohort study

NARCIS (Netherlands)

Feijen-de Jong, Esther I.; Jansen, Danielle E. M. C.; Baarveld, Frank; Spelten, Evelien; Schellevis, Francois; Reijneveld, Sijmen A.

2015-01-01

Background: Pregnant women visit complementary/alternative health care practitioners in addition to regular maternal health care practitioners. A wide variation has been reported with regard to rates and determinants of use of complementary/alternative medicine (CAM), which may be due to

Sex determination in Madagascar geckos of the genus Paroedura (Squamata: Gekkonidae): are differentiated sex chromosomes indeed so evolutionary stable?

Czech Academy of Sciences Publication Activity Database

Koubová, M.; Johnson Pokorná, Martina; Rovatsos, M.; Farkačová, K.; Altmanová, M.; Kratochvíl, L.

2014-01-01

Roč. 22, č. 4 (2014), s. 441-452 ISSN 0967-3849 R&D Projects: GA ČR GAP506/10/0718 Institutional support: RVO:67985904 Keywords : sex chromosomes * heterochromatin * reptiles * sex determination * FISH * ITSs Subject RIV: EG - Zoology Impact factor: 2.478, year: 2014

Molecular mechanisms of temperature-dependent sex determination in the context of ecological developmental biology.

Science.gov (United States)

Matsumoto, Yuiko; Crews, David

2012-05-06

Temperature-dependent sex determination (TSD) is a prime example of phenotypic plasticity in that gonadal sex is determined by the temperature of the incubating egg. In the red-eared slider turtle (Trachemys scripta), the effect of temperature can be overridden by exogenous ligands, i.e., sex steroid hormones and steroid metabolism enzyme inhibitors, during the temperature-sensitive period (TSP) of development. Precisely how the physical signal of temperature is transduced into a biological signal that ultimately results in sex determination remains unknown. In this review, we discuss the sex determining pathway underlying TSD by focusing on two candidate sex determining genes, Forkhead box protein L2 (FoxL2) and Doublesex mab3- related transcription factor 1 (Dmrt1). They appear to be involved in transducing the environmental temperature signal into a biological signal that subsequently determines gonadal sex. FoxL2 and Dmrt1 exhibit gonad-typical patterns of expression in response to temperature during the TSP in the red-eared slider turtle. Further, the biologically active ligands regulate the expression of FoxL2 and Dmrt1 during development to modify gonad trajectory. The precise regulatory mechanisms of expression of these genes by temperature or exogenous ligands are not clear. However, the environment often influences developmental gene expression by altering the epigenetic status in regulatory regions. Here, we will discuss if the regulation of FoxL2 and Dmrt1 expression by environment is mediated through epigenetic mechanisms during development in species with TSD. Published by Elsevier Ireland Ltd.

Abortion and sex determination: conflicting messages in information materials in a District of Rajasthan, India.

Science.gov (United States)

Nidadavolu, Vijaya; Bracken, Hillary

2006-05-01

Public information campaigns are an integral component of reproductive health programmes, including on abortion. In India, where sex selective abortion is increasing, public information is being disseminated on the illegality of sex determination. This paper presents findings from a study undertaken in 2003 in one district in Rajasthan to analyse the content of information materials on abortion and sex determination and people's perceptions of them. Most of the informational material about abortion was produced by one abortion service provider, but none by the public or private sector. The public sector had produced materials on the illegality of sex determination, some of which failed to distinguish between sex selection and other reasons for abortion. In the absence of knowledge of the legal status of abortion, the negative messages and strong language of these materials may have contributed to the perception that abortion is illegal in India. Future materials should address abortion and sex determination, including the legal status of abortion, availability of providers and social norms that shape decision-making. Married and unmarried women should be addressed and the participation of family members acknowledged, while supporting independent decisions by women. Sex determination should also be addressed, and the conditions under which a woman can and cannot seek an abortion clarified, using media and materials accessible to low-literate audiences. Based on what we learned in this research, a pictorial booklet and educator's manual were produced, covering both abortion and sex determination, and are being distributed in India.

Chromosome Banding in Amphibia. XXXVI. Multimorphic Sex Chromosomes and an Enigmatic Sex Determination in Eleutherodactylus johnstonei (Anura, Eleutherodactylidae).

Science.gov (United States)

Schmid, Michael; Steinlein, Claus

2018-01-01

A detailed cytogenetic study on the leaf litter frog Eleutherodactylus johnstonei from 14 different Caribbean islands and the mainlands of Venezuela and Guyana revealed the existence of multimorphic XY♂/XX♀ sex chromosomes 14. Their male sex determination and development depends either on the presence of 2 telocentric chromosomes 14 (XtYt), or on 1 submetacentric chromosome 14 (Xsm) plus 1 telocentric chromosome 14 (Yt), or on the presence of 2 submetacentric chromosomes 14 (XsmYsm). The female sex determination and development requires either the presence of 2 telocentric chromosomes 14 (XtXt) or 2 submetacentric chromosomes 14 (XsmXsm). In all individuals analyzed, the sex chromosomes 14 carry a prominent nucleolus organizer region in their long arms. An explanation is given for the origin of the (XtYt)♂, (XsmYt)♂, (XsmYsm)♂, (XtXt)♀, and (XsmXsm)♀ in the different populations of E. johnstonei. Furthermore, the present study gives detailed data on the chromosome banding patterns, in situ hybridization experiments, and the genome size of E. johnstonei. © 2018 S. Karger AG, Basel.

Sex determination of a Tunisian population by CT scan analysis of the skull.

Science.gov (United States)

Zaafrane, Malek; Ben Khelil, Mehdi; Naccache, Ines; Ezzedine, Ekbel; Savall, Frédéric; Telmon, Norbert; Mnif, Najla; Hamdoun, Moncef

2018-05-01

It is widely accepted that the estimation of biological attributes in the human skeleton is more accurate when population-specific standards are applied. With the shortage of such data for contemporary North African populations, it is duly required to establish population-specific standards. We present here the first craniometric standards for sex determination of a contemporary Tunisian population. The aim of this study was to analyze the correlation between sex and metric parameters of the skull in this population using CT scan analysis and to generate proper reliable standards for sex determination of a complete or fragmented skull. The study sample comprised cranial multislice computed tomography scans of 510 individuals equally distributed by sex. ASIR TM software in a General Electric TM workstation was used to position 37 landmarks along the volume-rendered images and the multiplanar slices, defining 27 inter-landmark distances. Frontal and parietal bone thickness was also measured for each case. The data were analyzed using basic descriptive statistics and logistic regression with cross-validation of classification results. All of the measurements were sexually dimorphic with male values being higher than female values. A nine-variable model achieved the maximum classification accuracy of 90% with -2.9% sex bias and a six-variable model yielded 85.9% sexing accuracy with -0.97% sex bias. We conclude that the skull is highly dimorphic and represents a reliable bone for sex determination in contemporary Tunisian individuals.

Delimitation of the embryonic thermosensitive period for sex determination using an embryo growth model reveals a potential bias for sex ratio prediction in turtles.

Science.gov (United States)

Girondot, Marc; Monsinjon, Jonathan; Guillon, Jean-Michel

2018-04-01

The sexual phenotype of the gonad is dependent on incubation temperature in many turtles, all crocodilians, and some lepidosaurians. At hatching, identification of sexual phenotype is impossible without sacrificing the neonates. For this reason, a general method to infer sexual phenotype from incubation temperatures is needed. Temperature influences sex determination during a specific period of the embryonic development, starting when the gonad begins to form. At constant incubation temperatures, this thermosensitive period for sex determination (TSP) is located at the middle third of incubation duration (MTID). When temperature fluctuates, the position of the thermosensitive period for sex determination can be shifted from the MTID because embryo growth is affected by temperature. A method is proposed to locate the thermosensitive period for sex determination based on modelling the embryo growth, allowing its precise identification from a natural regime of temperatures. Results from natural nests and simulations show that the approximation of the thermosensitive period for sex determination to the middle third of incubation duration may create a quasi-systematic bias to lower temperatures when computing the average incubation temperature during this period and thus a male-bias for sex ratio estimate. Copyright © 2018 Elsevier Ltd. All rights reserved.

Fgf9 and Wnt4 act as antagonistic signals to regulate mammalian sex determination.

Directory of Open Access Journals (Sweden)

Yuna Kim

2006-06-01

Full Text Available The genes encoding members of the wingless-related MMTV integration site (WNT and fibroblast growth factor (FGF families coordinate growth, morphogenesis, and differentiation in many fields of cells during development. In the mouse, Fgf9 and Wnt4 are expressed in gonads of both sexes prior to sex determination. Loss of Fgf9 leads to XY sex reversal, whereas loss of Wnt4 results in partial testis development in XX gonads. However, the relationship between these signals and the male sex-determining gene, Sry, was unknown. We show through gain- and loss-of-function experiments that fibroblast growth factor 9 (FGF9 and WNT4 act as opposing signals to regulate sex determination. In the mouse XY gonad, Sry normally initiates a feed-forward loop between Sox9 and Fgf9, which up-regulates Fgf9 and represses Wnt4 to establish the testis pathway. Surprisingly, loss of Wnt4 in XX gonads is sufficient to up-regulate Fgf9 and Sox9 in the absence of Sry. These data suggest that the fate of the gonad is controlled by antagonism between Fgf9 and Wnt4. The role of the male sex-determining switch--Sry in the case of mammals--is to tip the balance between these underlying patterning signals. In principle, sex determination in other vertebrates may operate through any switch that introduces an imbalance between these two signaling pathways.

The lesser known challenge of climate change: thermal variance and sex-reversal in vertebrates with temperature-dependent sex determination.

Directory of Open Access Journals (Sweden)

Jennifer L Neuwald

Full Text Available Climate change is expected to disrupt biological systems. Particularly susceptible are species with temperature-dependent sex determination (TSD, as in many reptiles. While the potentially devastating effect of rising mean temperatures on sex ratios in TSD species is appreciated, the consequences of increased thermal variance predicted to accompany climate change remain obscure. Surprisingly, no study has tested if the effect of thermal variance around high-temperatures (which are particularly relevant given climate change predictions has the same or opposite effects as around lower temperatures. Here we show that sex ratios of the painted turtle (Chrysemys picta were reversed as fluctuations increased around low and high unisexual mean-temperatures. Unexpectedly, the developmental and sexual responses around female-producing temperatures were decoupled in a more complex manner than around male-producing values. Our novel observations are not fully explained by existing ecological models of development and sex determination, and provide strong evidence that thermal fluctuations are critical for shaping the biological outcomes of climate change.

Differentiation of sex chromosomes and karyotypic evolution in the eye-lid geckos (Squamata: Gekkota: Eublepharidae), a group with different modes of sex determination.

Science.gov (United States)

Pokorná, Martina; Rábová, Marie; Ráb, Petr; Ferguson-Smith, Malcolm A; Rens, Willem; Kratochvíl, Lukáš

2010-11-01

The eyelid geckos (family Eublepharidae) include both species with temperature-dependent sex determination and species where genotypic sex determination (GSD) was suggested based on the observation of equal sex ratios at several incubation temperatures. In this study, we present data on karyotypes and chromosomal characteristics in 12 species (Aeluroscalabotes felinus, Coleonyx brevis, Coleonyx elegans, Coleonyx variegatus, Eublepharis angramainyu, Eublepharis macularius, Goniurosaurus araneus, Goniurosaurus lichtenfelderi, Goniurosaurus luii, Goniurosaurus splendens, Hemitheconyx caudicinctus, and Holodactylus africanus) covering all genera of the family, and search for the presence of heteromorphic sex chromosomes. Phylogenetic mapping of chromosomal changes showed a long evolutionary stasis of karyotypes with all acrocentric chromosomes followed by numerous chromosomal rearrangements in the ancestors of two lineages. We have found heteromorphic sex chromosomes in only one species, which suggests that sex chromosomes in most GSD species of the eyelid geckos are not morphologically differentiated. The sexual difference in karyotype was detected only in C. elegans which has a multiple sex chromosome system (X(1)X(2)Y). The metacentric Y chromosome evolved most likely via centric fusion of two acrocentric chromosomes involving loss of interstitial telomeric sequences. We conclude that the eyelid geckos exhibit diversity in sex determination ranging from the absence of any sexual differences to heteromorphic sex chromosomes, which makes them an interesting system for exploring the evolutionary origin of sexually dimorphic genomes.

Incubation temperature and gonadal sex affect growth and physiology in the leopard gecko (Eublepharis macularius), a lizard with temperature-dependent sex determination.

Science.gov (United States)

Tousignant, A; Crews, D

1995-05-01

Temperature-dependent sex determination (TSD), in which the temperature at which an egg incubates determines the sex of the individual, occurs in egg-laying reptiles of three separate orders. Previous studies have shown that the embryonic environment can have effects lasting beyond the period of sex determination. We investigated the relative roles of incubation temperature, exogenous estradiol, and gonadal sex (testis vs. ovary) in the differentiation of adult morphological and physiological traits of the leopard gecko, Eublepharis macularius. The results indicate that incubation temperature, steroid hormones, and gonads interact in the development of morphological and physiological characters with incubation temperature resulting in the greatest differences in adult phenotype. Incubation temperature did not affect reproductive success directly, but may influence offspring survival in natural situations through effects on adult female body size. Postnatal hormones seem to be more influential in the formation of adult phenotypes than prenatal hormones. These results demonstrate that TSD species can be used to investigate the effects of the physical environment on development in individuals without a predetermined genetic sex and thus provide further insight into the roles of gonadal sex and the embryonic environment in sexual differentiation.

Bombyx mori histone methyltransferase BmAsh2 is essential for silkworm piRNA-mediated sex determination.

Science.gov (United States)

Li, Zhiqian; You, Lang; Yan, Dong; James, Anthony A; Huang, Yongping; Tan, Anjiang

2018-02-01

Sex determination is a hierarchically-regulated process with high diversity in different organisms including insects. The W chromosome-derived Fem piRNA has been identified as the primary sex determination factor in the lepidopteran insect, Bombyx mori, revealing a distinctive piRNA-mediated sex determination pathway. However, the comprehensive mechanism of silkworm sex determination is still poorly understood. We show here that the silkworm PIWI protein BmSiwi, but not BmAgo3, is essential for silkworm sex determination. CRISPR/Cas9-mediated depletion of BmSiwi results in developmental arrest in oogenesis and partial female sexual reversal, while BmAgo3 depletion only affects oogenesis. We identify three histone methyltransferases (HMTs) that are significantly down-regulated in BmSiwi mutant moths. Disruption one of these, BmAsh2, causes dysregulation of piRNAs and transposable elements (TEs), supporting a role for it in the piRNA signaling pathway. More importantly, we find that BmAsh2 mutagenesis results in oogenesis arrest and partial female-to-male sexual reversal as well as dysregulation of the sex determination genes, Bmdsx and BmMasc. Mutagenesis of other two HMTs, BmSETD2 and BmEggless, does not affect piRNA-mediated sex determination. Histological analysis and immunoprecipitation results support a functional interaction between the BmAsh2 and BmSiwi proteins. Our data provide the first evidence that the HMT, BmAsh2, plays key roles in silkworm piRNA-mediated sex determination.

Bombyx mori histone methyltransferase BmAsh2 is essential for silkworm piRNA-mediated sex determination.

Directory of Open Access Journals (Sweden)

Zhiqian Li

2018-02-01

Full Text Available Sex determination is a hierarchically-regulated process with high diversity in different organisms including insects. The W chromosome-derived Fem piRNA has been identified as the primary sex determination factor in the lepidopteran insect, Bombyx mori, revealing a distinctive piRNA-mediated sex determination pathway. However, the comprehensive mechanism of silkworm sex determination is still poorly understood. We show here that the silkworm PIWI protein BmSiwi, but not BmAgo3, is essential for silkworm sex determination. CRISPR/Cas9-mediated depletion of BmSiwi results in developmental arrest in oogenesis and partial female sexual reversal, while BmAgo3 depletion only affects oogenesis. We identify three histone methyltransferases (HMTs that are significantly down-regulated in BmSiwi mutant moths. Disruption one of these, BmAsh2, causes dysregulation of piRNAs and transposable elements (TEs, supporting a role for it in the piRNA signaling pathway. More importantly, we find that BmAsh2 mutagenesis results in oogenesis arrest and partial female-to-male sexual reversal as well as dysregulation of the sex determination genes, Bmdsx and BmMasc. Mutagenesis of other two HMTs, BmSETD2 and BmEggless, does not affect piRNA-mediated sex determination. Histological analysis and immunoprecipitation results support a functional interaction between the BmAsh2 and BmSiwi proteins. Our data provide the first evidence that the HMT, BmAsh2, plays key roles in silkworm piRNA-mediated sex determination.

Sex determination using cheiloscopy and mandibular canine index as a tool in forensic dentistry

Directory of Open Access Journals (Sweden)

B Bhagyashree

2018-01-01

Full Text Available Identification of a person′s individuality and sex determination are important for legal as well as identification purposes. The aim of the present study was to check the reliability of cheiloscopy and mandibular canine index (MCI in the determination of sex in an individual. The aim of this study is to analyze different lip patterns reproduced by the natural dye (vermilion and lysochrome (Sudan Black II dyes and to compare the MCI in males and females for the determination of sex and to check the reliability of cheiloscopy and MCI for the same. Latent lip prints were developed using natural dye (vermilion and lysochrome (Sudan Black II dyes and their patterns categorized according to Tsuchihashi′s classification. MCI were calculated. Analysis of the two was performed. According to discriminant functional analysis, percentage accuracy for cheiloscopy in the determination of sex was found to be 55% while for MCI, the same value was 85%. Natural dye (vermilion was found as an efficient dye compared to lysochrome (Sudan Black II dyes for the development of latent lip prints. Both the dyes showed Type I lip print pattern to be common in males and females. Furthermore, all the parameters in MCI were found to be significant in the determination of sex in an individual. The results of the present study revealed MCI to be more reliable in the determination of sex than cheiloscopy.

Prevalence and determinants of online-sex use in the German population.

Directory of Open Access Journals (Sweden)

Manfred E Beutel

Full Text Available The unlimited access to sexual features in the World Wide Web has raised concerns about excessive and problematic online-sex use. However, little is known about antecedents of internet-sex use of different intensity. Based on a representative German sample of 2,522 participants between the ages of 14 and 97 years, the aims of the present study were (1 to determine the prevalence rates of online-sex users with the short version (ISSTGSV of the Internet Sex Screening Test and (2 to associate online-sex use with anxious vs. avoidant partner attachment patterns and "Big Five" personality traits as potential antecedents.The ISST is a brief, one-dimensional and reliable measure of online-sex activities (rtt = .69. Overall, 14.7% of respondents reported occasional and 4.2% intensive online-sex use. In multivariate analysis, online-sex use was significantly positively associated with male sex, younger age, unemployment and an anxious partner attachment pattern and negatively with conscientiousness and agreeableness.Arousal and satisfaction by virtual enactment of sexual phantasies may be attractive for anxiously attached persons who find it difficult to commit to a real life relationship due to fear of rejection or low self-esteem. More knowledge about the individual antecedents of intensive online-sex use may also be helpful for the development of consultation and treatment strategies for excessive and addictive online-sex use.

Prevalence and determinants of online-sex use in the German population.

Science.gov (United States)

Beutel, Manfred E; Giralt, Sebastian; Wölfling, Klaus; Stöbel-Richter, Yve; Subic-Wrana, Claudia; Reiner, Iris; Tibubos, Ana Nanette; Brähler, Elmar

2017-01-01

The unlimited access to sexual features in the World Wide Web has raised concerns about excessive and problematic online-sex use. However, little is known about antecedents of internet-sex use of different intensity. Based on a representative German sample of 2,522 participants between the ages of 14 and 97 years, the aims of the present study were (1) to determine the prevalence rates of online-sex users with the short version (ISSTGSV) of the Internet Sex Screening Test and (2) to associate online-sex use with anxious vs. avoidant partner attachment patterns and "Big Five" personality traits as potential antecedents. The ISST is a brief, one-dimensional and reliable measure of online-sex activities (rtt = .69). Overall, 14.7% of respondents reported occasional and 4.2% intensive online-sex use. In multivariate analysis, online-sex use was significantly positively associated with male sex, younger age, unemployment and an anxious partner attachment pattern and negatively with conscientiousness and agreeableness. Arousal and satisfaction by virtual enactment of sexual phantasies may be attractive for anxiously attached persons who find it difficult to commit to a real life relationship due to fear of rejection or low self-esteem. More knowledge about the individual antecedents of intensive online-sex use may also be helpful for the development of consultation and treatment strategies for excessive and addictive online-sex use.

Developmental Pathways from Parental Socioeconomic Status to Adolescent Substance Use: Alternative and Complementary Reinforcement.

Science.gov (United States)

Lee, Jungeun Olivia; Cho, Junhan; Yoon, Yoewon; Bello, Mariel S; Khoddam, Rubin; Leventhal, Adam M

2018-02-01

Although lower socioeconomic status has been linked to increased youth substance use, much less research has determined potential mechanisms explaining the association. The current longitudinal study tested whether alternative (i.e., pleasure gained from activities without any concurrent use of substances) and complementary (i.e., pleasure gained from activities in tandem with substance use) reinforcement mediate the link between lower socioeconomic status and youth substance use. Further, we tested whether alternative and complementary reinforcement and youth substance use gradually unfold over time and then intersect with one another in a cascading manner. Potential sex differences are also examined. Data were drawn from a longitudinal survey of substance use and mental health among high school students in Los Angeles. Data collection involved four semiannual assessment waves beginning in fall 2013 (N = 3395; M baseline age = 14.1; 47% Hispanic, 16.2% Asian, 16.1% multiethnic, 15.7% White, and 5% Black; 53.4% female). The results from a negative binomial path model suggested that lower parental socioeconomic status (i.e., lower parental education) was significantly related to an increased number of substances used by youth. The final path model revealed that the inverse association was statistically mediated by adolescents' diminished engagement in pleasurable substance-free activities (i.e., alternative reinforcers) and elevated engagement in pleasurable activities paired with substance use (i.e., complementary reinforcers). The direct effect of lower parental education on adolescent substance use was not statistically significant after accounting for the hypothesized mediating mechanisms. No sex differences were detected. Increasing access to and engagement in pleasant activities of high quality that do not need a reinforcement enhancer, such as substances, may be useful in interrupting the link between lower parental socioeconomic status and youth

Sex ratio variation and sex determination in Urtica dioica

NARCIS (Netherlands)

Glawe, Grit Anja

2006-01-01

This thesis will first document on variation in progeny sex ratios among individual female plants of Urtica dioica at our field site in Meijendel (Chapter 2). Next, we show that there is also considerable sex ratio variation among male and female flowering shoots in 26 natural populations studied

Feedback Control of Sex Determination by Dosage Compensation Revealed through Caenorhabditis Elegans Sdc-3 Mutations

OpenAIRE

DeLong, L.; Plenefisch, J. D.; Klein, R. D.; Meyer, B. J.

1993-01-01

In Caenorhabditis elegans, sex determination and dosage compensation are coordinately controlled through a group of genes that respond to the primary sex determination signal. Here we describe a new gene, sdc-3, that also controls these processes. In contrast to previously described genes, the sex determination and dosage compensation activities of sdc-3 are separately mutable, indicating that they function independently. Paradoxically, the sdc-3 null phenotype fails to reveal the role of sdc...

A NEW HYPOTHESIS ON THE EVOLUTION OF SEX DETERMINATION IN VERTEBRATES - BIG FEMALES ZW, BIG MALES XY

NARCIS (Netherlands)

KRAAK, SBM; DELOOZE, EMA

1993-01-01

Why are there two chromosomal sex-determining mechanisms in vertebrates; ZW/ZZ, meaning female heterogamety, and XX/XY, meaning male heterogamety? We propose an evolutionary explanation. Transition from environmental sex determination to genetic sex determination can result when an allele that

Sex-specific mechanism of social hierarchy in mice.

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van den Berg, Wouter E; Lamballais, Sander; Kushner, Steven A

2015-05-01

The establishment of social hierarchies is a naturally occurring, evolutionarily conserved phenomenon with a well-established impact on fitness and health. Investigations of complex social group dynamics may offer novel opportunities for translational studies of autism spectrum disorder. Here we describe a robust behavioral paradigm using an automated version of the tube test. Isogenic groups of male and female mice establish linear social hierarchies that remain highly stable for at least 14 days, the longest interval tested. Remarkably, however, their social strategy is sex-specific: females primarily utilize intrinsic attributes, whereas males are strongly influenced by prior social experience. Using both genetic and pharmacological manipulations, we identify testosterone as a critical sex-specific factor for determining which social strategy is used. Males inheriting a null mutation of the sex-determining region Y (Sry) gene used a similar social cognitive strategy as females. In contrast, females with transgenic expression of Sry utilized a typically male social strategy. Analogously, castration of males and testosterone supplementation of females yielded similar outcomes, with a reversal of their social cognitive strategy. Together, our results demonstrate a sex-specific mechanism underlying social hierarchy, in which both males and females retain the functional capacity to adapt their social strategy. More generally, we expect the automated tube test to provide an important complementary approach for both fundamental and translational studies of social behavior.

Constraints on temperature-dependent sex determination in the leopard gecko (Eublepharis macularius): response to Kratochvil et al.

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Huang, Victoria; Sakata, Jon T; Rhen, Turk; Coomber, Patricia; Simmonds, Sarah; Crews, David

2008-12-01

Kratochvil et al. (Naturwissenschaften 95:209-215, 2008) reported recently that in the leopard gecko (Eublepharis macularius) of the family Eublepharidae with temperature-dependent sex determination (TSD), clutches in which eggs were incubated at the same temperature produce only same-sex siblings. Interpreting this result in light of studies of sex steroid hormone involvement in sex determination, they suggested that maternally derived yolk steroid hormones could constrain sex-determining mechanisms in TSD reptiles. We have worked extensively with this species and have routinely incubated clutches at constant temperatures. To test the consistency of high frequency same-sex clutches across different incubation temperatures, we examined our records of clutches at the University of Texas at Austin from 1992 to 2001. We observed that clutches in which eggs were incubated at the same incubation temperature produced mixed-sex clutches as well as same-sex clutches. Furthermore, cases in which eggs within a clutch were separated and incubated at different temperatures produced the expected number of mixed-sex clutches. These results suggest that maternal influences on sex determination are secondary relative to incubation temperature effects.

Genetic architecture of sex determination in fish: Applications to sex ratio control in aquaculture

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Paulino eMartínez

2014-09-01

Full Text Available Controlling the sex ratio is essential in finfish farming. A balanced sex ratio is usually good for broodstock management, since it enables to develop appropriate breeding schemes. However, in some species the production of monosex populations is desirable because the existence of sexual dimorphism, primarily in growth or first time of sexual maturation, but also in color or shape, can render one sex more valuable. The knowledge of the genetic architecture of sex determination (SD is convenient for controlling sex ratio and for the implementation of breeding programs. Unlike mammals and birds, which show highly conserved master genes that control a conserved genetic network responsible for gonad differentiation (GD, a huge diversity of SD mechanisms has been reported in fish. Despite theory predictions, more than one gene is in many cases involved in fish SD and genetic differences have been observed in the GD network. Environmental factors also play a relevant role and epigenetic mechanisms are becoming increasingly recognized for the establishment and maintenance of the GD pathways. Although major genetic factors are frequently involved in fish SD, these observations strongly suggest that SD in this group resembles a complex trait. Accordingly, the application of quantitative genetics combined with genomic tools is desirable to address its study and in fact, when applied, it has frequently demonstrated a multigene trait interacting with environmental factors in model and cultured fish species. This scenario has notable implications for aquaculture and, depending upon the species, from chromosome manipulation or environmental control techniques up to classical selection or marker assisted selection programs, are being applied. In this review, we selected four relevant species or fish groups to illustrate this diversity and hence the technologies that can be used by the industry for the control of sex ratio: turbot and European sea bass, two

Sex determination and differentiation in Aurelia sp.1: the absence of temperature dependence

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Liu, Chunsheng; Gu, Zhifeng; Xing, Mengxin; Sun, Yun; Chen, Siqing; Chen, Zhaoting

2018-03-01

Cnidarians, being regarded as `basal' metazoan animals, are considered to have relatively high plasticity in terms of sex reversal. In this study we used an experimental approach to demonstrate sexual differentiation and plasticity in benthic polyps and pelagic medusae of Aurelia sp.1 maintained at different temperatures. Results indicated that in Aurelia sp.1, sex differentiation has been determined at the polyp stage and that all medusae originating from a given polyp are, phenotypically, of the same sex. In addition, the sex of polyps budding from the same clone (either male or female) at different temperatures appears to be the same as that of the parent. The sex of medusae that had originated from a known-sex polyp was observed to remain the same as that of the parent, irrespective of differences in strobilation or rearing temperatures. These results indicate that the mechanism of sex determination of Aurelia sp.1. is not influenced by prevailing temperature regimes. A comparison of variability in terms of sexual plasticity of Aurelia sp.1 with that of Hydrozoa and Anthozoa suggests that species characterized by a free-swimming medusa life stage have a high dispersal potential, which probably results in a lower rate of sex reversal.

Birth order, individual sex and sex of competitors determine the outcome of conflict among siblings over parental care

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Bonisoli-Alquati, Andrea; Boncoraglio, Giuseppe; Caprioli, Manuela; Saino, Nicola

2011-01-01

Success in competition for limiting parental resources depends on the interplay between parental decisions over allocation of care and offspring traits. Birth order, individual sex and sex of competing siblings are major candidates as determinants of success in sib–sib competition, but experimental studies focusing on the combined effect of these factors on parent–offspring communication and within-brood competitive dynamics are rare. Here, we assessed individual food intake and body mass gain during feeding trials in barn swallow chicks differing for seniority and sex, and compared the intensity of their acoustic and postural solicitation (begging) displays. Begging intensity and success in competition depended on seniority in combination with individual sex and sex of the opponent. Junior chicks begged more than seniors, independently of satiation level (which was also experimentally manipulated), and obtained greater access to food. Females were generally weaker competitors than males. Individual sex and sex of the opponent also affected duration of begging bouts. Present results thus show that competition with siblings can make the rearing environment variably harsh for developing chicks, depending on individual sex, sex of competing broodmates and age ranking within the nest. They also suggest that parental decisions on the allocation of care and response of kin to signalling siblings may further contribute to the outcome of sibling competition. PMID:20943688

Analysis of genes involved in sex determination of fishes by phenol-emulsion method

Energy Technology Data Exchange (ETDEWEB)

Nakayama, Ichiro; Nagoya, Hiroyuki; Okamoto, Hiroyuki; Araki, Kazuo [National Research Inst. of Aquaculture, Mie (Japan)

1998-02-01

With an aim to clarify the mechanism of sex determination common to vertebrates, the genes presumed to mediate the sex determination were analyzed through cDNA subtraction by phenol-emulsion method. A total RNA was extracted from male juvenile Amago, a kind of oncorhynchus and cDNA was synthesized using mRNA fractionated by oligo-dT column. The male-specific genes expressed in the stage of sex determination was isolated through incorporation to PVC-derived vector. Thus obtained genes were confirmed to be male-specific by Southern hybridization. The results of the screening for the subtracted products indicate that neither of the male-specific clones detected in this study was novel. Previous studies on sex discrimination based on mitochondrial DNA suggested that Sakuramasu and Amago belong in the same species, Oncorhynchus masou masou and the present results show that DNA sequence for male-derived GH pseudo-gene is partially different between the two fishes. (M.N.)

Sex determination in the Lesser Flamingo ( Phoenicopterus minor ...

African Journals Online (AJOL)

PCR amplification of the CHD-Z and CHD-W genes using DNA extracted from the blood samples was used to determine the sex of each bird. There were significant differences in mass and tarsus length among the three age groups, indicating that Lesser Flamingos continue to grow in skeletal size and mass between ...

Commentary Sex determination

Indian Academy of Sciences (India)

PRAKASH KUMAR G

2008-01-31

Jan 31, 2008 ... years old (Charnier 1966 reported it in an African agamid lizard), although it was ... people's attention in Susumu Ohno's now famous book on .... If they do enhance male and female fitness, sex chromosomes would then be.

B chromosomes have a functional effect on female sex determination in Lake Victoria cichlid fishes.

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Kohta Yoshida

2011-08-01

Full Text Available The endemic cichlid fishes in Lake Victoria are a model system for speciation through adaptive radiation. Although the evolution of the sex-determination system may also play a role in speciation, little is known about the sex-determination system of Lake Victoria cichlids. To understand the evolution of the sex-determination system in these fish, we performed cytogenetic analysis in 11 cichlid species from Lake Victoria. B chromosomes, which are present in addition to standard chromosomes, were found at a high prevalence rate (85% in these cichlids. In one species, B chromosomes were female-specific. Cross-breeding using females with and without the B chromosomes demonstrated that the presence of the B chromosomes leads to a female-biased sex ratio in this species. Although B chromosomes were believed to be selfish genetic elements with little effect on phenotype and to lack protein-coding genes, the present study provides evidence that B chromosomes have a functional effect on female sex determination. FISH analysis using a BAC clone containing B chromosome DNA suggested that the B chromosomes are derived from sex chromosomes. Determination of the nucleotide sequences of this clone (104.5 kb revealed the presence of several protein-coding genes in the B chromosome, suggesting that B chromosomes have the potential to contain functional genes. Because some sex chromosomes in amphibians and arthropods are thought to be derived from B chromosomes, the B chromosomes in Lake Victoria cichlids may represent an evolutionary transition toward the generation of sex chromosomes.

A heritable component in sex ratio and caste determination in a Cardiocondyla ant

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Heinze Jürgen

2009-10-01

Full Text Available Abstract Studies on sex ratios in social insects provide among the most compelling evidence for the importance of kin selection in social evolution. The elegant synthesis of Fisher's sex ratio principle and Hamilton's inclusive fitness theory predicts that colony-level sex ratios vary with the colonies' social and genetic structures. Numerous empirical studies in ants, bees, and wasps have corroborated these predictions. However, the evolutionary optimization of sex ratios requires genetic variation, but one fundamental determinant of sex ratios - the propensity of female larvae to develop into young queens or workers ("queen bias" - is thought to be largely controlled by the environment. Evidence for a genetic influence on sex ratio and queen bias is as yet restricted to a few taxa, in particular hybrids. Because of the very short lifetime of their queens, ants of the genus Cardiocondyla are ideal model systems for the study of complete lifetime reproductive success, queen bias, and sex ratios. We found that lifetime sex ratios of the ant Cardiocondyla kagutsuchi have a heritable component. In experimental single-queen colonies, 22 queens from a genetic lineage with a highly female-biased sex ratio produced significantly more female-biased offspring sex ratios than 16 queens from a lineage with a more male-biased sex ratio (median 91.5% vs. 58.5% female sexuals. Sex ratio variation resulted from different likelihood of female larvae developing into sexuals (median 50% vs. 22.6% female sexuals even when uniformly nursed by workers from another colony. Consistent differences in lifetime sex ratios and queen bias among queens of C. kagutsuchi suggest that heritable, genetic or maternal effects strongly affect caste determination. Such variation might provide the basis for adaptive evolution of queen and worker strategies, though it momentarily constrains the power of workers and queens to optimize caste ratios.

A heritable component in sex ratio and caste determination in a Cardiocondyla ant.

Science.gov (United States)

Frohschammer, Sabine; Heinze, Jürgen

2009-10-28

Studies on sex ratios in social insects provide among the most compelling evidence for the importance of kin selection in social evolution. The elegant synthesis of Fisher's sex ratio principle and Hamilton's inclusive fitness theory predicts that colony-level sex ratios vary with the colonies' social and genetic structures. Numerous empirical studies in ants, bees, and wasps have corroborated these predictions. However, the evolutionary optimization of sex ratios requires genetic variation, but one fundamental determinant of sex ratios - the propensity of female larvae to develop into young queens or workers ("queen bias") - is thought to be largely controlled by the environment. Evidence for a genetic influence on sex ratio and queen bias is as yet restricted to a few taxa, in particular hybrids.Because of the very short lifetime of their queens, ants of the genus Cardiocondyla are ideal model systems for the study of complete lifetime reproductive success, queen bias, and sex ratios. We found that lifetime sex ratios of the ant Cardiocondyla kagutsuchi have a heritable component. In experimental single-queen colonies, 22 queens from a genetic lineage with a highly female-biased sex ratio produced significantly more female-biased offspring sex ratios than 16 queens from a lineage with a more male-biased sex ratio (median 91.5% vs. 58.5% female sexuals). Sex ratio variation resulted from different likelihood of female larvae developing into sexuals (median 50% vs. 22.6% female sexuals) even when uniformly nursed by workers from another colony.Consistent differences in lifetime sex ratios and queen bias among queens of C. kagutsuchi suggest that heritable, genetic or maternal effects strongly affect caste determination. Such variation might provide the basis for adaptive evolution of queen and worker strategies, though it momentarily constrains the power of workers and queens to optimize caste ratios.

Observation of a ZZW female in a natural population: implications for avian sex determination.

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Arit, D; Bensch, S; Hansson, B; Hasselquist, D; Westerdahl, H

2004-01-01

Avian sex determination is chromosomal; however, the underlying mechanisms are not yet understood. There is no conclusive evidence for either of two proposed mechanisms: a dominant genetic switch or a dosage mechanism. No dominant sex-determining gene on the female-specific W chromosome has been found. Birds lack inactivation of one of the Z chromosomes in males, but seem to compensate for a double dose of Z-linked genes by other mechanisms. Recent studies showing female-specific expression of two genes may support an active role of the W chromosome. To resolve the question of avian sex determination the investigation of birds with a 2A: ZZW or 2A: ZO genotype would be decisive. Here, we report the case of an apparent 2A: ZZW great reed warbler (Acrocephalus arundinaceus) female breeding in a natural population, which was detected using Z-linked microsatellites. Our data strongly suggest a role of W-linked genes in avian sex determination. PMID:15252998

Missing female fetus: a micro level investigation of sex determination in a periurban area of Northern India.

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Ghosh, Rohini; Sharma, Arun Kumar

2012-01-01

A micro-level investigation of 983 pregnant women (aged 15-49 years) regarding sex determination and associated factors was carried out in a periurban region of Northern India. Among the women surveyed, 183 chose to use sex determination. The highest percentage of sex determination was among 30-39-year-old women, and general caste and family size were two risk factors associated with sex determination. Correcting imbalances in sex ratios at birth is a complex issue without easy answers, especially in patriarchal societies. Apart from raising awareness among decisionmakers, property rights in favor of women and strict vigilance and record of registration of ultrasound machines are necessary.

Canine index – A tool for sex determination

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Shankar M. Bakkannavar

2015-12-01

Full Text Available Teeth are most useful tools in victim identification in the living as well as the dead in the field of forensic investigations. Their ability to survive in situations like mass disasters makes them constructive devices. Many authors have measured crowns of teeth in both males and females and found certain variations. Canines, reported to survive in air crash and hurricane disasters, are perhaps the most stable teeth in the oral cavity because of the labiolingual thickness of the crown and the root anchorage in the alveolar process of jaws. Measurement of mesiodistal width of the mandibular canines and inter-canine distance of the mandible provides good evidence of sex identification due to dimorphism. This study was undertaken to evaluate the effectiveness of canine index (CI in the determination of sex.

Ocean acidification but not warming alters sex determination in the Sydney rock oyster, Saccostrea glomerata.

Science.gov (United States)

Parker, Laura M; O'Connor, Wayne A; Byrne, Maria; Dove, Michael; Coleman, Ross A; Pörtner, Hans-O; Scanes, Elliot; Virtue, Patti; Gibbs, Mitchell; Ross, Pauline M

2018-02-14

Whether sex determination of marine organisms can be altered by ocean acidification and warming during this century remains a significant, unanswered question. Here, we show that exposure of the protandric hermaphrodite oyster, Saccostrea glomerata to ocean acidification, but not warming, alters sex determination resulting in changes in sex ratios. After just one reproductive cycle there were 16% more females than males. The rate of gametogenesis, gonad area, fecundity, shell length, extracellular pH and survival decreased in response to ocean acidification. Warming as a sole stressor slightly increased the rate of gametogenesis, gonad area and fecundity, but this increase was masked by the impact of ocean acidification at a level predicted for this century. Alterations to sex determination, sex ratios and reproductive capacity will have flow on effects to reduce larval supply and population size of oysters and potentially other marine organisms. © 2018 The Author(s).

Heel–Ball index: An analysis of footprint dimensions for determination of sex

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Tanuj Kanchan

2014-06-01

Full Text Available Determination of sex from the footprints recovered at crime scenes can help the investigation by narrowing down the pool of possible suspects. The present research studies the dimensions of the heel and the ball in footprints, and derives the Heel–Ball (HB index from these foot dimensions with the aim to find out if the foot dimensions and the HB index exhibit sexual dimorphisms. The study was carried out on 100 individuals (50 males, 50 females of Indian origin. Footprints were obtained from both feet of the study participants using standard techniques. Thus, a total of 200 footprints were obtained. The breadth of the footprint at ball (BBAL and the breadth of the footprint at heel (BHEL were measured on the footprints. The HB index was derived as (BHEL ÷ BBAL × 100. The footprint measurements at the ball and heel were significantly larger in males on both the sides. Likewise, the derived HB index was larger in males in both feet, but the sex differences were not statistically significant. The study concludes that though footprint dimensions can be used in the determination of sex, the HB index may not be utilized in sex determination from footprints.

Sex determination from hand and foot dimensions in a North Indian population.

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Krishan, Kewal; Kanchan, Tanuj; Sharma, Abhilasha

2011-03-01

Hands and feet are often recovered from the site of natural as well as man-made disasters because of bomb blasts, train accidents, plane crashes, or mass homicides. This study is intended to establish standards for determination of sex from the dimensions of hands and feet in a North Indian population. The data for this study comprise 123 men and 123 women aged between 17 and 20 years from the "Rajput" population of Himachal Pradesh in North India. Four anthropometric measurements viz. hand length, hand breadth, foot length, and foot breadth have been taken on both sides of each subject following international anthropometric standards. The hand index (hand breadth/hand length × 100) and the foot index (foot breadth/foot length × 100) were calculated. Sectioning points and regression models are derived for the hand and foot dimensions and the derived indices. The hand and foot dimensions show a higher accuracy in sex determination by sectioning point analysis when compared to hand and foot index. Of the hand and the foot dimensions, hand breadth and foot breadth showed better accuracy in sex determination. Hand index and foot index remain poor sex discriminators in the study. © 2011 American Academy of Forensic Sciences.

Automatic Sex Determination of Skulls Based on a Statistical Shape Model

Directory of Open Access Journals (Sweden)

Li Luo

2013-01-01

Full Text Available Sex determination from skeletons is an important research subject in forensic medicine. Previous skeletal sex assessments are through subjective visual analysis by anthropologists or metric analysis of sexually dimorphic features. In this work, we present an automatic sex determination method for 3D digital skulls, in which a statistical shape model for skulls is constructed, which projects the high-dimensional skull data into a low-dimensional shape space, and Fisher discriminant analysis is used to classify skulls in the shape space. This method combines the advantages of metrical and morphological methods. It is easy to use without professional qualification and tedious manual measurement. With a group of Chinese skulls including 127 males and 81 females, we choose 92 males and 58 females to establish the discriminant model and validate the model with the other skulls. The correct rate is 95.7% and 91.4% for females and males, respectively. Leave-one-out test also shows that the method has a high accuracy.

Sex differences in adolescent depression: do sex hormones determine vulnerability?

NARCIS (Netherlands)

Naninck, E.F.G.; Lucassen, P.J.; Bakker, J.

2011-01-01

Depression is one of the most common, costly and severe psychopathologies worldwide. Its incidence, however, differs significantly between the sexes, and depression rates in women are twice those of men. Interestingly, this sex difference emerges during adolescence. Although the adolescent period is

Formal and informal sex education as determinants of premarital sexual behavior.

Science.gov (United States)

Spanier, G B

1976-01-01

Controversies exist regarding the effects of sex education in the schools and informal sex education obtained from parents, peers, the mass media, and other sources. Similarly, there is widespread interest in premarital sexual behavior, especially its determinants. This study presents several issues reflecting these concerns which have been the subject of much speculation but which have received little attention by researchers. The purpose of this study was to investigate--through the use of respondent reports--how formal and informal sex education influences premarital sexual behavior during college. A national probability sample of 1177 college students was studied using face-to-face interviews with approximately equal numbers of males and females. These interviews, which were conducted for the Institute for Sex Research, included questions about past and present sexual involvement and other attitudinal, behavioral and background variables. Accordingly, the data about sexual behavior and attitudes are based on the interviewees' self-reports. Indices were created which operationalized independent variables such as familial sexual conservatism, exposure to eroticism, perceived sex knowledge, and sexual exposure and assault during childhood and adolescence. Individual items reflecting childhood sex play, masturbation, current religiosity, religiosity while growing up, social class, sources of sex information, sex education in classrooms, and high school and college dating were used. The dependent variable, premarital sociosexual involvement, is a composite measure of incidence and prevalence of premarital heterosexual involvement which meets Guttman scaling criteria. An Automatic Interaction Detector analysis was used to determine the relative influences of reported sexualization variables on premarital sexual behavior. Major findings can be summarized as follows: Heterosexual behavior progresses in stepwise fashion from elementary to advanced levels of involvement

Sex determination in Turdus amaurochalinus (Passeriformes: Muscicapidae: morphometrical analysis supported by CHD gene

Directory of Open Access Journals (Sweden)

Katyucha Von Kossel de Andrade Silva

2011-06-01

Full Text Available Sex determination is important for conservation and population studies, particularly for reproduction programs of threatened species and behavioural ecology. Turdus amaurochalinus, Creamy-bellied Thrush, only exhibits sexual dimorphism during the breeding season, when males are considered to show intense yellow bills, and females and immature males show dark brown bills. The objectives of this study were: 1 to determine the sex of individuals using genetic techniques, and 2 to test the hypothesis that sex dimorphism can be detected by morphometry. This study was carried out at Parque Nacional da Restinga de Jurubatiba, a preserved area located on the North coast of Rio de Janeiro State. The birds were captured using ornithological nets, singly marked with metal rings, weighed, measured and had blood samples collected before being released. The sex of 42 T. amaurochalinus individuals was determined using the CHD gene marker. A total of 20 males and 22 females were identified from June to August, with peak capture frequency in June. Turdus amaurochalinus females and males differed significantly in morphometrical measures. The most important traits to distinguish males from females were wing length (Student t-test=4.34, df=40, p=0.0001 and weight (Student t-test=2.08,df=40, p=0.044: females were heavier and had significantly shorter wing length than males. Females and males were correctly classified in 86% and 75% of cases, respectively, using Discriminant Analysis. The molecular analysis was the most secure method for sex determination in the studied species. Rev. Biol. Trop. 59 (2: 789- 794. Epub 2011 June 01.

Exploring the envelope. Systematic alteration in the sex-determination system of the nematode caenorhabditis elegans.

OpenAIRE

Hodgkin, Jonathan

2002-01-01

The natural sexes of the nematode Caenorhabditis elegans are the self-fertilizing hermaphrodite (XX) and the male (XO). The underlying genetic pathway controlling sexual phenotype has been extensively investigated. Mutations in key regulatory genes have been used to create a series of stable populations in which sex is determined not by X chromosome dosage, but in a variety of other ways, many of which mimic the diverse sex-determination systems found in different animal species. Most of thes...

Three loci on mouse chromosome 5 and 10 modulate sex determination in XX Ods/+ mice.

Science.gov (United States)

Poirier, Christophe; Moran, Jennifer L; Kovanci, Ertug; Petit, Deborah C; Beier, David R; Bishop, Colin E

2007-07-01

In mouse, XY embryos are committed to the male sex determination pathway after the transient expression of the Y-linked Sry gene in the Sertoli cell lineage between 10.5 and 12.5 dpc. In the C57BL/6J strain, male sex determination program can be modulated by some autosomal genes. The C57BL/6J alleles at these autosomal loci can antagonize male sex determination in combination with specific Sry alleles. In this report, the authors have identified an effect of these C57BL/6J specific alleles in combination with a mutated Sox9 allele, Sox9(Ods). Authors report the mapping of three of these genetic loci on mouse chromosome 5 and 10 in a backcross of the Ods mutation to the C57BL/6J background. Our study confirms the importance of the strain C57BL/6J for the investigation of the genetic mechanisms that control sex determination.

Drosophila as a model for the study of sex determination in anopheline and aedine mosquitoes

International Nuclear Information System (INIS)

Pannuti, A.; Kocacitak, T.; Lucchesi, J.C.

2000-01-01

Sterile insect technique control strategies consist of releasing laboratory produced male insects that have been sterilised by irradiation. These strategies require the production of massive quantities of males. Population-replacement strategies rely on the genetically engineered interruption of that portion of the malaria parasite's life cycle that occurs in the mosquito. This could be achieved by the inundative introduction of transformed males or the more limited introduction of males carrying an infective agent capable of driving a parasite-inhibiting transgene into the vector population. Once again, the release of genetically engineered males would require genetic systems for their mass production. Mass production of males can be accomplished most effectively through genetic sexing techniques. Genetic sexing can be achieved by identifying the key steps in the genetic regulation of sex differentiation and by modifying one or more of these steps so that their execution would result in sex-specific lethality. As the necessary and seminal first step towards this goal, we set out to identify and isolate a gene whose primary transcript is processed differently in males and females of Anopheles gambiae Giles. A survey of sex determination among insects reveals a vast array of different mechanisms. Our understanding of these mechanisms consists only of information derived from classical cytological and genetic studies. Using the knowledge derived from the study of Drosophila, it has been possible to discern a fundamental pattern in the sex determining mechanisms of many diverse insect species (Noethiger and Steinmann-Zwicky 1985). The challenge now, is to determine if there has been an evolutionary conservation of the genes responsible for the fundamental pattern, i.e., if the molecular mechanisms that underlie sex determination in Drosophila are the same in other insects of interest or if in these insects, the apparent fundamental pattern is achieved by completely

Absolute determination of single-stranded and self-complementary adeno-associated viral vector genome titers by droplet digital PCR.

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Lock, Martin; Alvira, Mauricio R; Chen, Shu-Jen; Wilson, James M

2014-04-01

Accurate titration of adeno-associated viral (AAV) vector genome copies is critical for ensuring correct and reproducible dosing in both preclinical and clinical settings. Quantitative PCR (qPCR) is the current method of choice for titrating AAV genomes because of the simplicity, accuracy, and robustness of the assay. However, issues with qPCR-based determination of self-complementary AAV vector genome titers, due to primer-probe exclusion through genome self-annealing or through packaging of prematurely terminated defective interfering (DI) genomes, have been reported. Alternative qPCR, gel-based, or Southern blotting titering methods have been designed to overcome these issues but may represent a backward step from standard qPCR methods in terms of simplicity, robustness, and precision. Droplet digital PCR (ddPCR) is a new PCR technique that directly quantifies DNA copies with an unparalleled degree of precision and without the need for a standard curve or for a high degree of amplification efficiency; all properties that lend themselves to the accurate quantification of both single-stranded and self-complementary AAV genomes. Here we compare a ddPCR-based AAV genome titer assay with a standard and an optimized qPCR assay for the titration of both single-stranded and self-complementary AAV genomes. We demonstrate absolute quantification of single-stranded AAV vector genomes by ddPCR with up to 4-fold increases in titer over a standard qPCR titration but with equivalent readout to an optimized qPCR assay. In the case of self-complementary vectors, ddPCR titers were on average 5-, 1.9-, and 2.3-fold higher than those determined by standard qPCR, optimized qPCR, and agarose gel assays, respectively. Droplet digital PCR-based genome titering was superior to qPCR in terms of both intra- and interassay precision and is more resistant to PCR inhibitors, a desirable feature for in-process monitoring of early-stage vector production and for vector genome biodistribution

Computer-assisted sperm morphometry fluorescence-based analysis has potential to determine progeny sex.

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Santolaria, Pilar; Pauciullo, Alfredo; Silvestre, Miguel A; Vicente-Fiel, Sandra; Villanova, Leyre; Pinton, Alain; Viruel, Juan; Sales, Ester; Yániz, Jesús L

2016-01-01

This study was designed to determine the ability of computer-assisted sperm morphometry analysis (CASA-Morph) with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa (SX and SY, respectively). Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average (P potential to find differences between X- and Y-chromosome-bearing spermatozoa in bovine species although more studies are needed to increase the precision of sex determination by this technique.

The Sex Determination Gene transformer Regulates Male-Female Differences in Drosophila Body Size.

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Rideout, Elizabeth J; Narsaiya, Marcus S; Grewal, Savraj S

2015-12-01

Almost all animals show sex differences in body size. For example, in Drosophila, females are larger than males. Although Drosophila is widely used as a model to study growth, the mechanisms underlying this male-female difference in size remain unclear. Here, we describe a novel role for the sex determination gene transformer (tra) in promoting female body growth. Normally, Tra is expressed only in females. We find that loss of Tra in female larvae decreases body size, while ectopic Tra expression in males increases body size. Although we find that Tra exerts autonomous effects on cell size, we also discovered that Tra expression in the fat body augments female body size in a non cell-autonomous manner. These effects of Tra do not require its only known targets doublesex and fruitless. Instead, Tra expression in the female fat body promotes growth by stimulating the secretion of insulin-like peptides from insulin producing cells in the brain. Our data suggest a model of sex-specific growth in which body size is regulated by a previously unrecognized branch of the sex determination pathway, and identify Tra as a novel link between sex and the conserved insulin signaling pathway.

The Sex Determination Gene transformer Regulates Male-Female Differences in Drosophila Body Size.

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Elizabeth J Rideout

2015-12-01

Full Text Available Almost all animals show sex differences in body size. For example, in Drosophila, females are larger than males. Although Drosophila is widely used as a model to study growth, the mechanisms underlying this male-female difference in size remain unclear. Here, we describe a novel role for the sex determination gene transformer (tra in promoting female body growth. Normally, Tra is expressed only in females. We find that loss of Tra in female larvae decreases body size, while ectopic Tra expression in males increases body size. Although we find that Tra exerts autonomous effects on cell size, we also discovered that Tra expression in the fat body augments female body size in a non cell-autonomous manner. These effects of Tra do not require its only known targets doublesex and fruitless. Instead, Tra expression in the female fat body promotes growth by stimulating the secretion of insulin-like peptides from insulin producing cells in the brain. Our data suggest a model of sex-specific growth in which body size is regulated by a previously unrecognized branch of the sex determination pathway, and identify Tra as a novel link between sex and the conserved insulin signaling pathway.

Suitability of foramen magnum measurements in sex determination and their clinical significance.

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Tellioglu, A Metin; Durum, Y; Gok, M; Karakas, S; Polat, A G; Karaman, C Z

2018-01-01

The foramen magnum provides a transition between fossa cranii posterior and canalis vertebralis. Medulla oblongata, arteria vertebralis and nervus accessorius spinal part pass through the foramen magnum. In this study, we aimed to make the morphometric measurements of the foramen magnum on computed tomography (CT) and to determine the feasibility of sex determination based on these measurements. Besides sex determination, from a clinical aspect, it is important to know the measurements of the foramen magnum in the normal population in terms of diseases characterised by displacement of the posterior fossa structures through foramen magnum to upper cervical spinal canal such as Chiari malformations and syringomyelia. All the data for our study was obtained retrospectively from 100 patients (50 males, 50 females) who had a CT scan of the head and neck region in Adnan Menderes University Hospital, Department of Radiology. To examine the foramen magnum in each and every occipital bone, we measured the foramen magnum's anteroposterior diameter, transverse diameter, the area of the foramen magnum and its circumference. We found that men have a higher average value than women in our study. According to Student's t-test results; in all measured parameters, there is significant difference between the genders (p discriminant function test is performed for all four measurements, the discrimination rate is 64% for all women, 70% for all men and 67% for both genders. As a result of our study, the metric data we obtained will be useful in cases where the skeletons' sex could not be determined by any other methods. We believe that, our study may be useful for other studies in determining of sex from foramen magnum. Our measurements could give some information of the normal ranges of the foramen magnum in normal population, so that this can contribute to the diagnosis process of some diseases by imaging. (Folia Morphol 2018; 77, 1: 99-104).

Deciphering the link between doubly uniparental inheritance of mtDNA and sex determination in bivalves: Clues from comparative transcriptomics

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Capt, Charlotte; Renaut, Sébastien; Ghiselli, Fabrizio; Milani, Liliana; Johnson, Nathan A.; Sietman, Bernard E.; Stewart, Donald; Breton, Sophie

2018-01-01

Bivalves exhibit an astonishing diversity of sexual systems and sex-determining mechanisms. They can be gonochoric, hermaphroditic or androgenetic, with both genetic and environmental factors known to determine or influence sex. One unique sex-determining system involving the mitochondrial genome has also been hypothesized to exist in bivalves with doubly uniparental inheritance (DUI) of mtDNA. However, the link between DUI and sex determination remains obscure. In this study, we performed a comparative gonad transcriptomics analysis for two DUI-possessing freshwater mussel species to better understand the mechanisms underlying sex determination and DUI in these bivalves. We used a BLAST reciprocal analysis to identify orthologs between Venustaconcha ellipsiformis and Utterbackia peninsularis and compared our results with previously published sex-specific bivalve transcriptomes to identify conserved sex-determining genes. We also compared our data with other DUI species to identify candidate genes possibly involved in the regulation of DUI. A total of ∼12,000 orthologous relationships were found, with 2,583 genes differentially expressed in both species. Among these genes, key sex-determining factors previously reported in vertebrates and in bivalves (e.g., Sry, Dmrt1, Foxl2) were identified, suggesting that some steps of the sex-determination pathway may be deeply conserved in metazoans. Our results also support the hypothesis that a modified ubiquitination mechanism could be responsible for the retention of the paternal mtDNA in male bivalves, and revealed that DNA methylation could also be involved in the regulation of DUI. Globally, our results suggest that sets of genes associated with sex determination and DUI are similar in distantly-related DUI species.

Complementary sex determination in the parasitic wasp Diachasmimorpha longicaudata

Czech Academy of Sciences Publication Activity Database

Carabajal Paladino, Leonela Z.; Muntaabski, I.; Lanzavecchia, S.; Le Bagousse-Pinguet, Y.; Viscarret, M.; Juri, M.; Fueyo-Sánchez, L.; Papeschi, A.; Cladera, J.; Bressa, M. J.

2015-01-01

Roč. 10, č. 3 (2015), e0119619 E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Diachasmimorpha longicaudata Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.057, year: 2015 http://www.plosone.org/article/authors/info%3Adoi%2F10.1371%2Fjournal.pone.0119619

What was the ancestral sex-determining mechanism in amniote vertebrates?

Czech Academy of Sciences Publication Activity Database

Johnson Pokorná, Martina; Kratochvíl, L.

2016-01-01

Roč. 91, č. 1 (2016), s. 1-12 ISSN 1464-7931 R&D Projects: GA ČR GAP506/10/0718 Institutional support: RVO:67985904 Keywords : environmental sex determination * phylogeny * polyphenism Subject RIV: EG - Zoology Impact factor: 11.615, year: 2016

Sex determination from scapular length measurements by CT scans images in a Caucasian population.

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Giurazza, F; Schena, E; Del Vescovo, R; Cazzato, R L; Mortato, L; Saccomandi, P; Paternostro, F; Onofri, L; Zobel, B Beomonte

2013-01-01

Together with race, stature and age, sex is a main component of the biological identity. Thanks to its proportional correlation with parts of the human body, sex can be evaluated form the skeleton. The most accurate approach to determine sex by bone size is based on os coxae or skull. After natural disaster their presence can never be guaranteed, therefore the development of methods of sex determination using other skeletal elements can result crucial. Herein, sexual dimorphism in the human scapula is used to develop a two-variable discriminant function for sex estimation. We have enrolled 100 males and 100 females who underwent thoracic CT scan evaluation and we have estimated two scapular diameters. The estimation has been carried out by analyzing images of the scapulae of each patient after three dimensional post-processing reconstructions. The two-variable function allows to obtain an overall accuracy of 88% on the calibration sample. Furthermore, we have employed the mentioned function on a collection of 10 individual test sample from the collection of the "Museo di Anatomia Umana di Firenze" of the Università degli Studi di Firenze; sex has been correctly predicted on 9 skeletons.

Interactions of Socioeconomic Determinants, Offspring Sex Preference and Fertility Behavior

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Paul M. Sharp

2011-01-01

Full Text Available Using path anaysis and the 5% PUMS data of the 1990 and 2000 censuses, this study examines 1 the correlation between Chinese-American sex preference for children and their fertility behavior, and 2 the interaction between the sex preference and its socioeconomic determinants. Of normative and non-normative factors investegated in this study, offspring sex preference is the greatest stimulus to Chinese fertility. Of socioeconomic variables, women’s educational attainment plays a primary role in depressing the impact of son preference in addition to their increasing stay in the host society. However, these two factors do not work on their husbands in the same way, demonstrating men’s inflexible attitudes toward gender roles in the family and in society. Son preference exerts positive impact on American-Chinese fertility and prevent from further decline. Yet, the influence has been diminishing since 1990 as observed in this study.

Comparison of cranial sex determination by discriminant analysis and logistic regression.

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Amores-Ampuero, Anabel; Alemán, Inmaculada

2016-04-05

Various methods have been proposed for estimating dimorphism. The objective of this study was to compare sex determination results from cranial measurements using discriminant analysis or logistic regression. The study sample comprised 130 individuals (70 males) of known sex, age, and cause of death from San José cemetery in Granada (Spain). Measurements of 19 neurocranial dimensions and 11 splanchnocranial dimensions were subjected to discriminant analysis and logistic regression, and the percentages of correct classification were compared between the sex functions obtained with each method. The discriminant capacity of the selected variables was evaluated with a cross-validation procedure. The percentage accuracy with discriminant analysis was 78.2% for the neurocranium (82.4% in females and 74.6% in males) and 73.7% for the splanchnocranium (79.6% in females and 68.8% in males). These percentages were higher with logistic regression analysis: 85.7% for the neurocranium (in both sexes) and 94.1% for the splanchnocranium (100% in females and 91.7% in males).

Sex determination mode does not affect body or genital development of the central bearded dragon (Pogona vitticeps

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Sarah L. Whiteley

2017-12-01

Full Text Available Abstract Background The development of male- or female-specific phenotypes in squamates is typically controlled by either temperature-dependent sex determination (TSD or chromosome-based genetic sex determination (GSD. However, while sex determination is a major switch in individual phenotypic development, it is unknownhow evolutionary transitions between GSD and TSD might impact on the evolution of squamate phenotypes, particularly the fast-evolving and diverse genitalia. Here, we take the unique opportunity of studying the impact of both sex determination mechanisms on the embryological development of the central bearded dragon (Pogona vitticeps. This is possible because of the transitional sex determination system of this species, in which genetically male individuals reverse sex at high incubation temperatures. This can trigger the evolutionary transition of GSD to TSD in a single generation, making P. vitticeps an ideal model organism for comparing the effects of both sex determination processes in the same species. Results We conducted four incubation experiments on 265 P. vitticeps eggs, covering two temperature regimes (“normal” at 28 °C and “sex reversing” at 36 °C and the two maternal sexual genotypes (concordant ZW females or sex-reversed ZZ females. From this, we provide the first detailed staging system for the species, with a focus on genital and limb development. This was augmented by a new sex chromosome identification methodology for P. vitticeps that is non-destructive to the embryo. We found a strong correlation between embryo age and embryo stage. Aside from faster growth in 36 °C treatments, body and external genital development was entirely unperturbed by temperature, sex reversal or maternal sexual genotype. Unexpectedly, all females developed hemipenes (the genital phenotype of adult male P. vitticeps, which regress close to hatching. Conclusions The tight correlation between embryo age and embryo stage

Sex determination from the radius and ulna in a modern South African sample.

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Barrier, I L O; L'Abbé, E N

2008-07-18

With a large number of unidentified skeletal remains found in South Africa, the development of population specific osteometric standards is imperative. Forensic anthropologists need to have access to a variety of techniques to establish accurate demographic profiles from complete, fragmentary and/or commingled remains. No research has been done on the forearm of African samples, even though these bones have been shown to exhibit sexual dimorphism. The purpose of this paper is to develop discriminant function formulae to determine sex from the radius and ulna in a South African population. The sample consisted of 200 male and 200 female skeletons from the Pretoria Bone (University of Pretoria) and Raymond A. Dart (Witwatersrand University) collections. Sixteen standard anthropometric measurements were taken from the radius (9) and ulna (7) and subjected to stepwise and direct discriminant function analysis. Distal breadth, minimum mid-shaft diameter and maximum head diameter were the best discriminators of sex for the radius, while minimum mid-shaft diameter and olecranon breadth were selected for the ulna. Classification accuracy for the forearm ranged from 76 to 86%. The radius and ulna can be considered moderate discriminators for determining sex in a South African group. However, it is advised that these formulae are used in conjunction with additional methods to determine sex.

Tribolium castaneum Transformer-2 regulates sex determination and development in both males and females.

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Shukla, Jayendra Nath; Palli, Subba Reddy

2013-12-01

Tribolium castaneum Transformer (TcTra) is essential for female sex determination and maintenance through the regulation of sex-specific splicing of doublesex (dsx) pre-mRNA. In females, TcTra also regulates the sex-specific splicing of its own pre-mRNA to ensure continuous production of functional Tra protein. Transformer protein is absent in males and hence dsx pre-mRNA is spliced in a default mode. The mechanisms by which males inhibit the production of functional Tra protein are not known. Here, we report on functional characterization of transformer-2 (tra-2) gene (an ortholog of Drosophila transformer-2) in T. castaneum. RNA interference-mediated knockdown in the expression of gene coding for tra-2 in female pupae or adults resulted in the production of male-specific isoform of dsx and both female and male isoforms of tra suggesting that Tra-2 is essential for the female-specific splicing of tra and dsx pre-mRNAs. Interestingly, knockdown of tra-2 in males did not affect the splicing of dsx but resulted in the production of both female and male isoforms of tra suggesting that Tra-2 suppresses female-specific splicing of tra pre-mRNA in males. This dual regulation of sex-specific splicing of tra pre-mRNA ensures a tight regulation of sex determination and maintenance. These data suggest a critical role for Tra-2 in suppression of female sex determination cascade in males. In addition, RNAi studies showed that Tra-2 is also required for successful embryonic and larval development in both sexes. Copyright © 2013 Elsevier Ltd. All rights reserved.

Possibility of Morphometrical Determining of Sex of Steppe Eagle Nestlings from Western and Eastern Populations?

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Igor V. Karyakin

2018-03-01

Full Text Available Sexual dimorphism among nestlings of the Steppe Eagle (Aquila nipalensis is poorly manifested. Thus, determining of sex by morphometric methods encountered many difficulties and could be completed only by the most experienced ornithologists who knows the species very well. This article presents a morphometric method for determining sex of nestlings of the Steppe Eagles from different breeding populations that belongs to different size classes. The method is based on classification formula obtained via linear discriminant analysis conducted for the data set of measurements of Steppe Eagle’s nestlings from Central Kazakhstan and Altai Republic in 2017. To control the sex determination of nestlings a molecular-genetics method was used.

Yolk-albumen testosterone in a lizard with temperature-dependent sex determination: relation with development.

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Huang, Victoria; Bowden, Rachel M; Crews, David

2013-06-01

The leopard gecko (Eublepharis macularius) exhibits temperature-dependent sex determination as well as temperature-influenced polymorphisms. Research suggests that in oviparous reptiles with temperature-dependent sex determination, steroid hormones in the yolk might influence sex determination and sexual differentiation. From captive leopard geckos that were all from the same incubation temperature regime, we gathered freshly laid eggs, incubated them at one of two female-biased incubation temperatures (26 or 34°C), and measured testosterone content in the yolk-albumen at early or late development. No differences in the concentration of testosterone were detected in eggs from different incubation temperatures. We report testosterone concentrations in the yolk-albumen were higher in eggs of late development than early development at 26°C incubation temperatures, a finding opposite that reported in other TSD reptiles studied to date. Copyright © 2013. Published by Elsevier Inc.

Application of three-dimensional reconstruction technology in establishment of atlas space model and sex determination

International Nuclear Information System (INIS)

Zhou Jianying; Tian Yong; He Qing; Li Youqiong; Han Qing; Cheng Kailiang

2013-01-01

Objective: To establish the method of using the atlas morphological indexes for sex determination in Jilin province and to evaluate its effect. Methods: The clinic neck CT images were used to reconstruct the 3D image of atlas. A total of 27 linear measurement on 8 aspects of the atlas were measured and the ratios were calculated. The 14 items were selected. Results: Of the total 27 linear measurements, 14 were sexually dimorphic (P<0.05), and the accuracies of sex determination of 27 indexes were 52.0% -89.3% . The highest accuracy was width of vertebral body (86.7% ). A function with variables predicting sex with 96.8% accuracy was derived by using stepwise method of discriminant function analysis: Y=1.308W - 0.409CDF - 0.469LTPSD - 0.849LUACD + 0.478RUACD + 0.332RDACD + 0.363ATH - 0.334PTH - 0.236PAL. Conclusion: The method of using atlas traits for sex determination in Jilin province is practicable. (authors)

Determinants of condom breakage among female sex workers in Karnataka, India

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Bradley Janet

2011-12-01

Full Text Available Abstract Background Condoms are effective in preventing the transmission of HIV and other sexually transmitted infections, when properly used. However, recent data from surveys of female sex workers (FSWs in Karnataka in south India, suggest that condom breakage rates may be quite high. It is important therefore to quantify condom breakage rates, and examine what factors might precipitate condom breakage, so that programmers can identify those at risk, and develop appropriate interventions. Methods We explored determinants of reported condom breakage in the previous month among 1,928 female sex workers in four districts of Karnataka using data from cross-sectional surveys undertaken from July 2008 to February 2009. Using stepwise multivariate logistic regression, we examined the possible determinants of condom breakage, controlling for several independent variables including the district and client load. Results Overall, 11.4% of FSWs reported at least one condom break in the previous month. FSWs were much more likely to report breakage if under 20 years of age (AOR 3.43, p = 0.005; if divorced/ separated/widowed (AOR 1.52, p = 0.012; if they were regular alcohol users (AOR 1.63, p = 0.005; if they mostly entertained clients in lodges/rented rooms (AOR 2.99, p = 0.029 or brothels (AOR 4.77, p = 0.003, compared to street based sex workers; if they had ever had anal sex (AOR 2.03, p = 0.006; if the sex worker herself (as opposed to the client applied the condom at last use (AOR 1.90, p Conclusions The reported incidence of condom breakage was high in this study, and this is a major concern for HIV/STI prevention programs, for which condom use is a key prevention tool. Younger and more marginalized female sex workers were most vulnerable to condom breakage. Special effort is therefore required to seek out such women and to provide information and skills on correct condom use. More research is also needed on what specific situational parameters

Computer-assisted sperm morphometry fluorescence-based analysis has potential to determine progeny sex

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Pilar Santolaria

2016-01-01

Full Text Available This study was designed to determine the ability of computer-assisted sperm morphometry analysis (CASA-Morph with fluorescence to discriminate between spermatozoa carrying different sex chromosomes from the nuclear morphometrics generated and different statistical procedures in the bovine species. The study was divided into two experiments. The first was to study the morphometric differences between X- and Y-chromosome-bearing spermatozoa (SX and SY, respectively. Spermatozoa from eight bulls were processed to assess simultaneously the sex chromosome by FISH and sperm morphometry by fluorescence-based CASA-Morph. SX cells were larger than SY cells on average (P < 0.001 although with important differences between bulls. A simultaneous evaluation of all the measured features by discriminant analysis revealed that nuclear area and average fluorescence intensity were the variables selected by stepwise discriminant function analysis as the best discriminators between SX and SY. In the second experiment, the sperm nuclear morphometric results from CASA-Morph in nonsexed (mixed SX and SY and sexed (SX semen samples from four bulls were compared. FISH allowed a successful classification of spermatozoa according to their sex chromosome content. X-sexed spermatozoa displayed a larger size and fluorescence intensity than nonsexed spermatozoa (P < 0.05. We conclude that the CASA-Morph fluorescence-based method has the potential to find differences between X- and Y-chromosome-bearing spermatozoa in bovine species although more studies are needed to increase the precision of sex determination by this technique.

Contribution of complementary foods to the total daily water needs of urban Guatemalan infants

NARCIS (Netherlands)

Enneman, A.; Campos, R.; Hernandez, L.; Palma, A.V.; Vossenaar, M.; Solomons, N.W.

2010-01-01

Background: Estimates of adequate intake (AI) for water only became available in 2005. The daily water AI for 6-12-month-old infants of both sexes is 800 mL. The present study aimed to estimate the water intake of urban infants receiving both breast milk and complementary feeding (CF) and to compare

Complementary and alternative medicine use in children with thalassaemia.

Science.gov (United States)

Efe, Emine; Işler, Ayşegül; Sarvan, Süreyya; Başer, Hayriye; Yeşilipek, Akif

2013-03-01

The aims of this study were to: (1) determine the types of complementary and alternative medicine use among children with thalassaemia as reported by parents and (2) describe sociodemographic and medical factors associated with the use of such treatments in families residing in southern Turkey. Thalassaemia is one of the most common human genetic diseases. Despite the therapeutic efforts, patients will encounter a variety of physical and psychological problems. Therefore, the use of complementary and alternative medicines among children thalassaemia is becoming increasingly popular. This is a descriptive study of complementary and alternative medicine. This study was conducted in the Hematology Outpatient Clinic at Akdeniz University Hospital and in the Thalassemia Centre at Ministry of Health Antalya Education and Research Hospital, Antalya, Turkey, between January 2010-December 2010. Parents of 97 paediatric patients, among 125 parents who applied to the haematology outpatient clinic and thalassaemia centre between these dates, agreed to take part in the study with whom contact could be made were included. Data were collected by using a questionnaire. The proportion of parents who reported using one or more of the complementary and alternative medicine methods was 82·5%. Of these parents, 61·8% were using prayer/spiritual practice, 47·4% were using nutritional supplements and 35·1% were using animal materials. It was determined that a significant portion of the parents using complementary and alternative medicine use it to treat their children's health problems, they were informed about complementary and alternative medicine by their paediatricians and family elders, and they have discussed the use of complementary and alternative medicine with healthcare professionals. To sustain medical treatment and prognosis of thalassaemia, it is important for nurses to consult with their patients and parents regarding the use and potential risks of some complementary

Multilocus Sex Determination Revealed in Two Populations of Gynodioecious Wild Strawberry, Fragaria vesca subsp. bracteata.

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Ashman, Tia-Lynn; Tennessen, Jacob A; Dalton, Rebecca M; Govindarajulu, Rajanikanth; Koski, Matthew H; Liston, Aaron

2015-10-19

Gynodioecy, the coexistence of females and hermaphrodites, occurs in 20% of angiosperm families and often enables transitions between hermaphroditism and dioecy. Clarifying mechanisms of sex determination in gynodioecious species can thus illuminate sexual system evolution. Genetic determination of gynodioecy, however, can be complex and is not fully characterized in any wild species. We used targeted sequence capture to genetically map a novel nuclear contributor to male sterility in a self-pollinated hermaphrodite of Fragaria vesca subsp. bracteata from the southern portion of its range. To understand its interaction with another identified locus and possibly additional loci, we performed crosses within and between two populations separated by 2000 km, phenotyped the progeny and sequenced candidate markers at both sex-determining loci. The newly mapped locus contains a high density of pentatricopeptide repeat genes, a class commonly involved in restoration of fertility caused by cytoplasmic male sterility. Examination of all crosses revealed three unlinked epistatically interacting loci that determine sexual phenotype and vary in frequency between populations. Fragaria vesca subsp. bracteata represents the first wild gynodioecious species with genomic evidence of both cytoplasmic and nuclear genes in sex determination. We propose a model for the interactions between these loci and new hypotheses for the evolution of sex determining chromosomes in the subdioecious and dioecious Fragaria. Copyright © 2015 Ashman et al.

Manipulation of arthropod sex determination by endosymbionts : Diversity and molecular mechanisms

NARCIS (Netherlands)

Ma, W. -J.; Vavre, F.; Beukeboom, L. W.

2014-01-01

Arthropods exhibit a large variety of sex determination systems both at the chromosomal and molecular level. Male heterogamety, female heterogamety, and haplodiploidy occur frequently, but partially different genes are involved. Endosymbionts, such as Wolbachia, Cardinium, Rickettsia, and

Use of complementary and alternative medicine in Europe: Health-related and sociodemographic determinants.

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Kemppainen, Laura M; Kemppainen, Teemu T; Reippainen, Jutta A; Salmenniemi, Suvi T; Vuolanto, Pia H

2017-10-01

The aim of this research was to study health-related and sociodemographic determinants of the use of different complementary and alternative medicine (CAM) treatments in Europe and differences in CAM use in various European countries. The study was based on a design-based logistic regression analysis of the European Social Survey (ESS), Round 7. We distinguished four CAM modalities: manual therapies, alternative medicinal systems, traditional Asian medical systems and mind-body therapies. In total, 25.9% of the general population had used CAM during the last 12 months. Typically, only one CAM treatment had been used, and it was used more often as complementary rather than alternative treatment. The use of CAM varied greatly by country, from 10% in Hungary to almost 40% in Germany. Compared to those in good health, the use of CAM was two to fourfold greater among those with health problems. The health profiles of users of different CAM modalities varied. For example, back or neck pain was associated with all types of CAM, whereas depression was associated only with the use of mind-body therapies. Individuals with difficult to diagnose health conditions were more inclined to utilize CAM, and CAM use was more common among women and those with a higher education. Lower income was associated with the use of mind-body therapies, whereas the other three CAM modalities were associated with higher income. Help-seeking differed according to the health problem, something that should be acknowledged by clinical professionals to ensure safe care. The findings also point towards possible socioeconomic inequalities in health service use.

Genetic and physical maps around the sex-determining M-locus of the dioecious plant asparagus.

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Telgmann-Rauber, Alexa; Jamsari, Ari; Kinney, Michael S; Pires, J Chris; Jung, Christian

2007-09-01

Asparagus officinalis L. is a dioecious plant. A region called the M-locus located on a pair of homomorphic sex chromosomes controls the sexual dimorphism in asparagus. The aim of this work was to clone the region determining sex in asparagus from its position in the genome. The structure of the region encompassing M should be investigated and compared to the sex-determining regions in other dioecious model species. To establish an improved basis for physical mapping, a high-resolution genetic map was enriched with AFLP markers closely linked to the target locus by carrying out a bulked segregant analysis. By screening a BAC library with AFLP- and STS-markers followed by chromosome walking, a physical map with eight contigs could be established. However, the gaps between the contigs could not be closed due to a plethora of repetitive elements. Surprisingly, two of the contigs on one side of the M-locus did not overlap although they have been established with two markers, which mapped in a distance as low as 0.25 cM flanking the sex locus. Thus, the clustering of the markers indicates a reduced recombination frequency within the M-region. On the opposite side of the M-locus, a contig was mapped in a distance of 0.38 cM. Four closely linked BAC clones were partially sequenced and 64 putative ORFs were identified. Interestingly, only 25% of the ORFs showed sequence similarity to known proteins and ESTs. In addition, an accumulation of repetitive sequences and a low gene density was revealed in the sex-determining region of asparagus. Molecular cytogenetic and sequence analysis of BACs flanking the M-locus indicate that the BACs contain highly repetitive sequences that localize to centromeric and pericentromeric locations on all asparagus chromosomes, which hindered the localization of the M-locus to the single pair of sex chromosomes. We speculate that dioecious Silene, papaya and Asparagus species may represent three stages in the evolution of XX, XY sex

MYB transcription factor gene involved in sex determination in Asparagus officinalis.

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Murase, Kohji; Shigenobu, Shuji; Fujii, Sota; Ueda, Kazuki; Murata, Takanori; Sakamoto, Ai; Wada, Yuko; Yamaguchi, Katsushi; Osakabe, Yuriko; Osakabe, Keishi; Kanno, Akira; Ozaki, Yukio; Takayama, Seiji

2017-01-01

Dioecy is a plant mating system in which individuals of a species are either male or female. Although many flowering plants evolved independently from hermaphroditism to dioecy, the molecular mechanism underlying this transition remains largely unknown. Sex determination in the dioecious plant Asparagus officinalis is controlled by X and Y chromosomes; the male and female karyotypes are XY and XX, respectively. Transcriptome analysis of A. officinalis buds showed that a MYB-like gene, Male Specific Expression 1 (MSE1), is specifically expressed in males. MSE1 exhibits tight linkage with the Y chromosome, specific expression in early anther development and loss of function on the X chromosome. Knockout of the MSE1 orthologue in Arabidopsis induces male sterility. Thus, MSE1 acts in sex determination in A. officinalis. © 2016 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

A Novel Candidate Gene for Temperature-Dependent Sex Determination in the Common Snapping Turtle

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Schroeder, Anthony L.; Metzger, Kelsey J.; Miller, Alexandra; Rhen, Turk

2016-01-01

Temperature-dependent sex determination (TSD) was described nearly 50 years ago. Researchers have since identified many genes that display differential expression at male- vs. female-producing temperatures. Yet, it is unclear whether these genes (1) are involved in sex determination per se, (2) are downstream effectors involved in differentiation of ovaries and testes, or (3) are thermo-sensitive but unrelated to gonad development. Here we present multiple lines of evidence linking CIRBP to sex determination in the snapping turtle, Chelydra serpentina. We demonstrate significant associations between a single nucleotide polymorphism (SNP) (c63A > C) in CIRBP, transcript levels in embryonic gonads during specification of gonad fate, and sex in hatchlings from a thermal regime that produces mixed sex ratios. The A allele was induced in embryos exposed to a female-producing temperature, while expression of the C allele did not differ between female- and male-producing temperatures. In accord with this pattern of temperature-dependent, allele-specific expression, AA homozygotes were more likely to develop ovaries than AC heterozygotes, which, in turn, were more likely to develop ovaries than CC homozygotes. Multiple regression using SNPs in CIRBP and adjacent loci suggests that c63A > C may be the causal variant or closely linked to it. Differences in CIRBP allele frequencies among turtles from northern Minnesota, southern Minnesota, and Texas reflect small and large-scale latitudinal differences in TSD pattern. Finally, analysis of CIRBP protein localization reveals that CIRBP is in a position to mediate temperature effects on the developing gonads. Together, these studies strongly suggest that CIRBP is involved in determining the fate of the bipotential gonad. PMID:26936926

Temperature-dependent sex determination modulates cardiovascular maturation in embryonic snapping turtles Chelydra serpentina.

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Alvine, Travis; Rhen, Turk; Crossley, Dane A

2013-03-01

We investigated sex differences in cardiovascular maturation in embryos of the snapping turtle Chelydra serpentina, a species with temperature-dependent sex determination. One group of eggs was incubated at 26.5°C to produce males. Another group of eggs was incubated at 26.5°C until embryos reached stage 17; eggs were then shifted to 31°C for 6 days to produce females, and returned to 26.5°C for the rest of embryogenesis. Thus, males and females were at the same temperature when autonomic tone was determined and for most of development. Cholinergic blockade increased resting blood pressure (P(m)) and heart rate (f(H)) in both sexes at 75% and 90% of incubation. However, the magnitude of the f(H) response was enhanced in males compared with females at 90% of incubation. β-adrenergic blockade increased P(m) at 75% of incubation in both sexes but had no effect at 90% of incubation. β-adrenergic blockade reduced f(H) at both time points but produced a stronger response at 90% versus 75% of incubation. We found that α-adrenergic blockade decreased P(m) in both sexes at 75% and 90% of incubation and decreased f(H) at 75% of incubation in both sexes. At 90% of incubation, f(H) decreased in females but not males. Although these data clearly demonstrate sexual dimorphism in the autonomic regulation of cardiovascular physiology in embryos, further studies are needed to test whether differences are caused by endocrine signals from gonads or by a hormone-independent temperature effect.

Determinants of complementary feeding practices among mothers of 6-24 months failure to thrive children based on behavioral analysis phase of PRECEDE model, Tehran.

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Shams, Nasibeh; Mostafavi, Firoozeh; Hassanzadeh, Akbar

2016-01-01

This study intended to clarify the determining factors of complementary feeding practices among Tehran 6-24 months failure to thrive children in order to use the results for planning the interventions to reduce the possible adverse effects. In this study, 132 mothers of three medical and health centers were chosen by random sampling among those centers operating under the supervision of south of Tehran District Health Center and study data were collected from them. A valid and reliable questionnaire as a data collection instrument developed based on behavioral analysis phase of PRECEDE model. Spearman and Pearson's correlation coefficient test were used to determine the statistical relationship between factors associated with complementary feeding practices among mothers. The mothers' knowledge was as follows: 0.8%, 20.4%, and 78.8% of them were good, medium, and poor, respectively. Mean scores for the mothers' performance in terms of supplementary feeding was 66.8. Pearson correlation indicated a positive and significant correlation between the mothers' performance with enabling and reinforcing factors, but there wasn't any significant relationship between the mothers' performance and knowledge about complementary feeding. According to the obtained results, reinforcing factors, and enabling factors are associated with the mothers' performance in terms of complementary feeding. Hence, attention to these issues is essential for better health interventions planning.

Use of radioimmunoassay procedures for the determination of sex hormones in animal tissues

International Nuclear Information System (INIS)

Hoffmann, B.

1983-01-01

Radioimmunoassay methods for the determination of sex steroids and other compounds with sex hormone-like activities in various edible animal tissues and endocrine glands have been developed. Reliability of these methods, allowing quantification in a range of 10 -11 M, has been adequately demonstrated. When applied to monitoring residues of anabolic sex hormones in edible tissues of veal calves, physiological baseline levels of some endogenous ''anabolic'' steroids (like testosterone, oestrogens) were established; in the case of xenobiotics residues at the scheduled time of slaughter could be quantified (trenbolone) and a regulatory method to implement the ban of diethylstilbestrol was introduced. (author)

Methyl farnesoate synthesis is necessary for the environmental sex determination in the water flea Daphnia pulex.

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Toyota, Kenji; Miyakawa, Hitoshi; Hiruta, Chizue; Furuta, Kenjiro; Ogino, Yukiko; Shinoda, Tetsuro; Tatarazako, Norihisa; Miyagawa, Shinichi; Shaw, Joseph R; Iguchi, Taisen

2015-09-01

Sex-determination systems can be divided into two groups: genotypic sex determination (GSD) and environmental sex determination (ESD). ESD is an adaptive life-history strategy that allows control of sex in response to environmental cues in order to optimize fitness. However, the molecular basis of ESD remains largely unknown. The micro crustacean Daphnia pulex exhibits ESD in response to various external stimuli. Although methyl farnesoate (MF: putative juvenile hormone, JH, in daphnids) has been reported to induce male production in daphnids, the role of MF as a sex-determining factor remains elusive due to the lack of a suitable model system for its study. Here, we establish such a system for ESD studies in D. pulex. The WTN6 strain switches from producing females to producing males in response to the shortened day condition, while the MFP strain only produces females, irrespective of day-length. To clarify whether MF has a novel physiological role as a sex-determining factor in D. pulex, we demonstrate that a MF/JH biosynthesis inhibitor suppressed male production in WTN6 strain reared under the male-inducible condition, shortened day-length. Moreover, we show that juvenile hormone acid O-methyltransferase (JHAMT), a critical enzyme of MF/JH biosynthesis, displays MF-generating activity by catalyzing farnesoic acid. Expression of the JHAMT gene increased significantly just before the MF-sensitive period for male production in the WTN6 strain, but not in the MFP strain, when maintained under male-inducible conditions. These results suggest that MF synthesis regulated by JHAMT is necessary for male offspring production in D. pulex. Our findings provide novel insights into the genetic underpinnings of ESD and they begin to shed light on the physiological function of MF as a male-fate determiner in D. pulex. Copyright © 2015 Elsevier Ltd. All rights reserved.

Liquid chromatographic determination of saccharin in beverages and desserts: complementary collaborative study.

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Sjöberg, A M

1988-01-01

A complementary collaborative study was conducted on a liquid chromatographic method for determination of saccharin in accordance with the latest international recommendations. One industrial and 6 official food control laboratories analyzed 3 samples of a juice, a soft drink, and a dessert at concentration levels of 26-90 mg/L, 33-73 mg/L, and 56-147 mg/kg, respectively. Blind duplicates and a blank were supplied for each type of material at each concentration level. The beverage was chromatographed directly and the dessert was extracted with ethanol before chromatography. Average recoveries were 95-107%. The reproducibility relative standard deviations were 6.4-7.3% for the juice, 9.2-20.6% for the soft drink, and 13.4-16.2% for the dessert. The outlier percentage was 14.3%. The results were compared with those of an earlier collaborative study by Nordic laboratories and with general collaborative results obtained by AOAC.

Sex determination using facial linear dimensions and angles among Hausa population of Kano State, Nigeria

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Lawan H. Adamu

2016-12-01

Full Text Available The aim of the study was to determine sexual dimorphism as well as to predict sex using facial linear dimensions and angles among Hausas of Kano state Nigeria. A total of 283 subjects comprising 147 males and 136 females age range 18–25 years participated. Photographs methods were used to capture the face. Independent sample t-test was used to test for sex differences in the variables. Binary logistic regression was applied to obtain a predicting equation (BLR model for sex. The predicted probabilities of BLR were analyzed using receiver operating characteristic curve. The results showed that all the facial linear dimensions showed significance sexual dimorphism except interocular distance, upper facial width, philtrum length, lower vermilion width, left and right orbital width. With regards to sex prediction, upper facial height was the single best predictor of sex with an accuracy of 76.2% and 24–33% contribution to the prediction. However, the percentage accuracy increased to 91% when six variables were pooled together in the equations. For facial angles, only nasion and aperture modified angle did not show significant gender differences. However, in the variables with significant sexual dimorphism only nasomental angle showed a significant level of sex prediction with an accuracy of 70.3%. In conclusion, sex discrimination using facial linear dimensions and angles was well established in this study. The sex of an individual of Hausa ethnic group can be determined using facial linear dimensions. Dispite sexual dimorphsm shown by facial angles, only nasomental angle was good discriminator of sex.

Determinants of Heterosexual Adolescents Having Sex with Female Sex Workers in Singapore.

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Junice Y S Ng

Full Text Available We assessed the proportion of and socio-ecological factors associated with ever having had sex with female sex workers (FSWs among heterosexual adolescents. We also described the characteristics of the adolescents who reported inconsistent condom use with FSWs.This is a cross-sectional study (response rate: 73% of 300 heterosexually active male adolescents of 16 to 19 years attending a national STI clinic in Singapore between 2009 and 2014. We assessed the ecological factors (individual, parental, peer, school and medial influences and sexual risk behaviors using a self-reported questionnaire. Poisson regression was used to obtain the adjusted prevalence ratios (aPR and confidence intervals (CI.The proportion of heterosexual male adolescents who had ever had sex with FSWs was 39%. Multivariate analysis showed that significant factors associated with ever having had sex with FSWs were sex initiation before 16 years old (aPR 1.79 CI: 1.30-2.46, never had a sexually active girlfriend (aPR 1.75 CI 1.28-2.38, reported lower self-esteem score (aPR 0.96 CI: 0.93-0.98, higher rebelliousness score (aPR 1.03 CI: 1.00-1.07 and more frequent viewing of pornography (aPR 1.47 CI: 1.04-2.09. Lifetime inconsistent condom use with FSWs was 30%.A significant proportion of heterosexual male adolescents attending the public STI clinic had ever had sex with FSWs. A targeted intervention that addresses different levels of influence to this behavior is needed. This is even more so because a considerable proportion of adolescents reported inconsistent condom use with FSWs, who may serve as a bridge of STI transmission to the community. National surveys on adolescent health should include the assessment of frequency of commercial sex visits and condom use with FSWs for long-term monitoring and surveillance.

Determinants of condom breakage among female sex workers in Karnataka, India.

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Bradley, Janet; Rajaram, S; Alary, Michel; Isac, Shajy; Washington, Reynold; Moses, Stephen; Ramesh, B M

2011-12-29

Condoms are effective in preventing the transmission of HIV and other sexually transmitted infections, when properly used. However, recent data from surveys of female sex workers (FSWs) in Karnataka in south India, suggest that condom breakage rates may be quite high. It is important therefore to quantify condom breakage rates, and examine what factors might precipitate condom breakage, so that programmers can identify those at risk, and develop appropriate interventions. We explored determinants of reported condom breakage in the previous month among 1,928 female sex workers in four districts of Karnataka using data from cross-sectional surveys undertaken from July 2008 to February 2009. Using stepwise multivariate logistic regression, we examined the possible determinants of condom breakage, controlling for several independent variables including the district and client load. Overall, 11.4% of FSWs reported at least one condom break in the previous month. FSWs were much more likely to report breakage if under 20 years of age (AOR 3.43, p = 0.005); if divorced/ separated/widowed (AOR 1.52, p = 0.012); if they were regular alcohol users (AOR 1.63, p = 0.005); if they mostly entertained clients in lodges/rented rooms (AOR 2.99, p = 0.029) or brothels (AOR 4.77, p = 0.003), compared to street based sex workers; if they had ever had anal sex (AOR 2.03, p = 0.006); if the sex worker herself (as opposed to the client) applied the condom at last use (AOR 1.90, p < 0.001); if they were inconsistent condom users (AOR 2.77, p < 0.001); and if they had never seen a condom demonstration (AOR 2.37, p < 0.001). The reported incidence of condom breakage was high in this study, and this is a major concern for HIV/STI prevention programs, for which condom use is a key prevention tool. Younger and more marginalized female sex workers were most vulnerable to condom breakage. Special effort is therefore required to seek out such women and to provide information and skills on correct

Sexy transgenes: the impact of gene transfer and gene inactivation technologies on the understanding of mammalian sex determination.

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Vaiman, Daniel

2003-06-01

Amongst the various developmental pathways ending in a sound mammal, sex determination presents the peculiarity of a choice between two equally viable options: female or male. Therefore, destroying a 'male-determining gene' or a 'female-determining gene' should generally not be lethal. Genetic sex determination is divided into two consecutive steps: construction of the bipotential gonad, and then sex determination per se. The genes involved in the first step are in fact involved in the development of various body compartments, and their mutation is generally far from innocuous. From transgenic and inactivation studies carried out on the laboratory mouse, a complete picture of the two steps is beginning to emerge, where the gonad itself and the necessary ducts are shown to evolve in a very coordinate way, with well-defined sex-specificities. Compared with testis determination, the ovarian side of the picture is still relatively empty, but this situation can change rapidly as candidate ovarian genes for inactivation studies are beginning to be identified.

Plasticity of gene-regulatory networks controlling sex determination: of masters, slaves, usual suspects, newcomers, and usurpators.

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Herpin, Amaury; Schartl, Manfred

2015-10-01

Sexual dimorphism is one of the most pervasive and diverse features of animal morphology, physiology, and behavior. Despite the generality of the phenomenon itself, the mechanisms controlling how sex is determined differ considerably among various organismic groups, have evolved repeatedly and independently, and the underlying molecular pathways can change quickly during evolution. Even within closely related groups of organisms for which the development of gonads on the morphological, histological, and cell biological level is undistinguishable, the molecular control and the regulation of the factors involved in sex determination and gonad differentiation can be substantially different. The biological meaning of the high molecular plasticity of an otherwise common developmental program is unknown. While comparative studies suggest that the downstream effectors of sex-determining pathways tend to be more stable than the triggering mechanisms at the top, it is still unclear how conserved the downstream networks are and how all components work together. After many years of stasis, when the molecular basis of sex determination was amenable only in the few classical model organisms (fly, worm, mouse), recently, sex-determining genes from several animal species have been identified and new studies have elucidated some novel regulatory interactions and biological functions of the downstream network, particularly in vertebrates. These data have considerably changed our classical perception of a simple linear developmental cascade that makes the decision for the embryo to develop as male or female, and how it evolves. © 2015 The Authors.

Phenotypic differences in teeth dimensions among Chennai population: An aid in sex determination

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Sreedevi Dharman

2015-01-01

Full Text Available Objective: To investigate the presence of sexual dimorphism by studying the size of the teeth among males and females in Chennai population, which aids in sex determination. Materials and Methods: Incisocervical length, mesiodistal and buccolingual diameters were measured in teeth of 60 subjects (30 males, 30 females in the age group of 18-22 years from Chennai population. The differences in the mean values of parameters in males and females were calculated using independent t-test. Discriminant functional analysis was performed to determine the accuracy of sex. Results: Significant differences were found in mean incisocervical length which were found to be larger in males with P < 0.05 in 11, 12, 14, 17, 21, 22, 24, 26, 27, 31, 32, 33, 34, 41, 43, and 45 and with P < 0.001 in 13, 23, 32, 42, 43, and 44, with the exception of 37 and 47 which were larger in females. Mean mesiodistal diameter was larger in males with P < 0.05 in 11, 12, and 21 and with P < 0.001 in 13, 23, 33, and 43. Mean buccolingual diameter was larger in males with P < 0.05 in 12, 21, 31, 33, and 41 and with P < 0.001 in 11, 13, 23, and 43. Accuracy rate of predicting sex based on incisocervical length (17, 23, 47 and mesiodistal diameter (13, 33 was 78.3% and based on buccolingual diameter (13 was 76.7%. Conclusion: Males showed greater sexual dimorphism than females. Application of incisocervical, mesiodistal, and buccolingual dimensional variability among males and females in the Chennai population can aid in sex determination in forensic odontology, as the results showed moderate extent of dimorphism with an overall accuracy rate of predicting sex to be 78%.

Mapping and validation of the major sex-determining region in Nile tilapia (Oreochromis niloticus L. Using RAD sequencing.

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Christos Palaiokostas

Full Text Available Sex in Oreochromis niloticus (Nile tilapia is principally determined by an XX/XY locus but other genetic and environmental factors also influence sex ratio. Restriction Associated DNA (RAD sequencing was used in two families derived from crossing XY males with females from an isogenic clonal line, in order to identify Single Nucleotide Polymorphisms (SNPs and map the sex-determining region(s. We constructed a linkage map with 3,802 SNPs, which corresponded to 3,280 informative markers, and identified a major sex-determining region on linkage group 1, explaining nearly 96% of the phenotypic variance. This sex-determining region was mapped in a 2 cM interval, corresponding to approximately 1.2 Mb in the O. niloticus draft genome. In order to validate this, a diverse family (4 families; 96 individuals in total and population (40 broodstock individuals test panel were genotyped for five of the SNPs showing the highest association with phenotypic sex. From the expanded data set, SNPs Oni23063 and Oni28137 showed the highest association, which persisted both in the case of family and population data. Across the entire dataset all females were found to be homozygous for these two SNPs. Males were heterozygous, with the exception of five individuals in the population and two in the family dataset. These fish possessed the homozygous genotype expected of females. Progeny sex ratios (over 95% females from two of the males with the "female" genotype indicated that they were neomales (XX males. Sex reversal induced by elevated temperature during sexual differentiation also resulted in phenotypic males with the "female" genotype. This study narrows down the region containing the main sex-determining locus, and provides genetic markers tightly linked to this locus, with an association that persisted across the population. These markers will be of use in refining the production of genetically male O. niloticus for aquaculture.

Non-invasive prenatal diagnosis for fetal sex determination: benefits and disadvantages from the service users' perspective.

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Lewis, Celine; Hill, Melissa; Skirton, Heather; Chitty, Lyn S

2012-11-01

Prenatal fetal sex determination is clinically indicated for women who are at risk of having a child with a serious genetic disorder affecting a particular sex. Ultrasound has been the traditional method used, but early fetal sex determination using non-invasive prenatal diagnosis (NIPD) can now be performed using cell-free fetal DNA in maternal plasma. The study aim was to assess the views and experiences of service users who had used NIPD for fetal sex determination. In this paper, we report on the perceived benefits and disadvantages. A qualitative approach using semi-structured interviews was used. A total of 44 participants (38 women and 6 partners of participating women) were recruited. Participants' views and experiences of NIPD were overwhelmingly positive. Concerning benefits over traditional methods, three themes emerged: (1) technical aspects of technology; (2) timing; and (3) enhanced decision-making. Practical advantages of NIPD included avoiding miscarriage, and there were a number of psychological advantages associated with timing such as perceived control, early re-engagement, normalization of pregnancy and peace of mind. Participants also valued NIPD as it enabled a stepwise approach to decision-making. A number of disadvantages were discussed including concerns about social sexing and increased bonding at a time in pregnancy when miscarriage risk is high. However, participants felt these were fairly minor in comparison with the advantages of NIPD. Until definitive genetic diagnosis using NIPD is available, NIPD for fetal sex determination is perceived as a good interim measure with a number of notable advantages over traditional methods.

Non-invasive prenatal diagnosis for fetal sex determination: benefits and disadvantages from the service users' perspective

Science.gov (United States)

Lewis, Celine; Hill, Melissa; Skirton, Heather; Chitty, Lyn S

2012-01-01

Prenatal fetal sex determination is clinically indicated for women who are at risk of having a child with a serious genetic disorder affecting a particular sex. Ultrasound has been the traditional method used, but early fetal sex determination using non-invasive prenatal diagnosis (NIPD) can now be performed using cell-free fetal DNA in maternal plasma. The study aim was to assess the views and experiences of service users who had used NIPD for fetal sex determination. In this paper, we report on the perceived benefits and disadvantages. A qualitative approach using semi-structured interviews was used. A total of 44 participants (38 women and 6 partners of participating women) were recruited. Participants' views and experiences of NIPD were overwhelmingly positive. Concerning benefits over traditional methods, three themes emerged: (1) technical aspects of technology; (2) timing; and (3) enhanced decision-making. Practical advantages of NIPD included avoiding miscarriage, and there were a number of psychological advantages associated with timing such as perceived control, early re-engagement, normalization of pregnancy and peace of mind. Participants also valued NIPD as it enabled a stepwise approach to decision-making. A number of disadvantages were discussed including concerns about social sexing and increased bonding at a time in pregnancy when miscarriage risk is high. However, participants felt these were fairly minor in comparison with the advantages of NIPD. Until definitive genetic diagnosis using NIPD is available, NIPD for fetal sex determination is perceived as a good interim measure with a number of notable advantages over traditional methods. PMID:22453293

Sex-specific markers developed by next-generation sequencing confirmed an XX/XY sex determination system in bighead carp (Hypophthalmichehys nobilis) and silver carp (Hypophthalmichthys molitrix).

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Liu, Haiyang; Pang, Meixia; Yu, Xiaomu; Zhou, Ying; Tong, Jingou; Fu, Beide

2018-01-05

Sex-specific markers are powerful tools for identifying sex-determination system in various animals. Bighead carp (Hypophthalmichehys nobilis) and silver carp (Hypophthalmichthys molitrix) are two of the most important edible fish in Asia, which have a long juvenility period that can lasts for 4-5 years. In this study, we found one sex-specific marker by next-generation sequencing together with bioinformatics analysis in bighead carp. The male-specific markers were used to perform molecular sexing in the progenies of artificial gynogenetic diploids and found all progenies (n = 160) were females. Meanwhile, around 1 : 1 sex ratio was observed in a total of 579 juvenile offspring from three other families. To further extend the male-specific region, we performed genome walking and got a male-specific sequence of 8,661 bp. Five pairs of primers were designed and could be used to efficiently distinguish males from females in bighead carp and silver carp. The development of these male-specific markers and results of their molecular sexing in different populations provide strong evidence for a sex determination system of female homogametry or male heterogametry (XX/XY) in bighead carp and silver carp. To the best of our knowledge, this is the first report of effective sex-specific markers in these two large carp species. © The Author(s) 2018. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

Sex Determination from Fragmented and Degenerated DNA by Amplified Product-Length Polymorphism Bidirectional SNP Analysis of Amelogenin and SRY Genes.

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Kotoka Masuyama

Full Text Available Sex determination is important in archeology and anthropology for the study of past societies, cultures, and human activities. Sex determination is also one of the most important components of individual identification in criminal investigations. We developed a new method of sex determination by detecting a single-nucleotide polymorphism in the amelogenin gene using amplified product-length polymorphisms in combination with sex-determining region Y analysis. We particularly focused on the most common types of postmortem DNA damage in ancient and forensic samples: fragmentation and nucleotide modification resulting from deamination. Amplicon size was designed to be less than 60 bp to make the method more useful for analyzing degraded DNA samples. All DNA samples collected from eight Japanese individuals (four male, four female were evaluated correctly using our method. The detection limit for accurate sex determination was determined to be 20 pg of DNA. We compared our new method with commercial short tandem repeat analysis kits using DNA samples artificially fragmented by ultraviolet irradiation. Our novel method was the most robust for highly fragmented DNA samples. To deal with allelic dropout resulting from deamination, we adopted "bidirectional analysis," which analyzed samples from both sense and antisense strands. This new method was applied to 14 Jomon individuals (3500-year-old bone samples whose sex had been identified morphologically. We could correctly identify the sex of 11 out of 14 individuals. These results show that our method is reliable for the sex determination of highly degenerated samples.

Use of radioimmunoassay procedures for the determination of sex hormones in animal tissues

Energy Technology Data Exchange (ETDEWEB)

Hoffmann, B. (Institut fuer Veterinaermedizin des Bundesgesundheitsamtes (Robert von Ostertag-Institut), Berlin (Germany, F.R.))

1983-07-01

Radioimmunoassay methods for the determination of sex steroids and other compounds with sex hormone-like activities in various edible animal tissues and endocrine glands have been developed. Reliability of these methods, allowing quantification in a range of 10/sup -11/ M, has been adequately demonstrated. When applied to monitoring residues of anabolic sex hormones in edible tissues of veal calves, physiological baseline levels of some endogenous ''anabolic'' steroids (like testosterone, oestrogens) were established; in the case of xenobiotics residues at the scheduled time of slaughter could be quantified (trenbolone) and a regulatory method to implement the ban of diethylstilbestrol was introduced.

Determination of sex-ratio by birth order in an urban community in Manipur.

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Brogen, Akoijam S; Shantibala, K; Rajkumari, Bishwalata; Laishram, Jalina

2009-01-01

To determine the sex ratio by birth order and to assess the sex preference of the couples in an urban community. A cross sectional study, in an urban community in Manipur, was conducted among the currently married couples. Data on background characteristics of the couple, family pedigree chart (of the offspring) including history of abortion, stillbirth, death of child of the couple, sex preference and Pre-natal Diagnostic Techniques (Regulation and Prevention of Misuse) Act [PNDT Act] were collected through a structured interview. Data were analyzed using descriptive and chi-square statistics. There were a total of 1777 births to the 855 couples interviewed. There were 900 females per 1000 males for the 1st birth order but the sex ratio was favorable towards females in the 2nd, 3rd and 4th birth orders. Among both the husbands and wives, being more educated was significantly associated (p<0.05) with preferring lesser number of children, using new technology for sex selection and having heard of the PNDT Act. Majority of those who wanted to use new technology for sex selection (128, 56.6%) preferred to have male child. Sex ratio in this community was favorable towards females, though it was less among the first born babies.

Impact and determinants of sex preference in Nepal.

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Leone, Tiziana; Matthews, Zoë; Dalla Zuanna, Gianpiero

2003-06-01

Gender discrimination and son preference are key demographic features of South Asia and are well documented for India. However, gender bias and sex preference in Nepal have received little attention. 1996 Nepal Demographic and Health Survey data on ever-married women aged 15-49 who did not desire any more children were used to investigate levels of gender bias and sex preference. The level of contraceptive use and the total fertility rate in the absence of sex preference were estimated, and logistic regression was performed to analyze the association between socioeconomic and demographic variables and stopping childbearing after the birth of a son. Commonly used indicators of gender bias, such as sex ratio at birth and sex-specific immunization rates, do not suggest a high level of gender discrimination in Nepal. However, sex preference decreases contraceptive use by 24% and increases the total fertility rate by more than 6%. Women's contraceptive use, exposure to the media, parity, last birth interval, educational level and religion are linked to stopping childbearing after the birth of a boy, as is the ethnic makeup of the local area. The level of sex preference in Nepal is substantial. Sex preference is an important barrier to the increase of contraceptive use and decline of fertility in the country; its impact will be greater as desired family size declines.

Fetal sex determination in the first trimester of pregnancy using a Y chromosome-specific DNA probe

Energy Technology Data Exchange (ETDEWEB)

Zeng, Y.; Huang, S.; Chen, M.; Huang, Y.; Zhang, M.; Dong, J.; Ku, A.; Xu, S.

1987-05-01

Prenatal determination of fetal sex is important for the prevention of X-linked disorders such as hemophilia, Lesch-Nyhan syndrome and Duchenne muscular dystrophy. The complex procedures of prenatal diagnosis for X-linked disorders are unnecessary if the fetus is female, because usually no clinical symptoms ever appear in female. pY 3.4 probe used in this work for sex determination is a 3.4 kilobase human repeat sequence. The probe is specific for the Y chromosome of males and can be used for sex determination. The other prove pBLUR used in this paper as control is a widely dispersed, highly repeated human Alu family DNA sequence, represented equally in male and female DNA. On the basis of the relative densities of the autoradiographic spots produced by hybridization of fetal DNA with pY3.4 and pBLUR, the sex of fetus can be clearly identified. Further the authors can determine the radioactive intensity (cpm) of the hybridized DNA spots and the ratio of hybridization with Y3.4 to pBLUR (Y3.4/pBLUR x 10). Results show that the hybridization ratio of DNA from chorionic villi of male (1.03 +/- 0.24) is significantly higher than that of female (0.16 +/- 0.09). Therefore, sex determination of the fetus can be made, based on the ratio of pY3.4/pBLUR x 10. If necessary they can also use Southern hybridization with pY 3.4 probe of DNA isolated from chorionic villi to confirm the result of dot hybridization.

Nucleotide variability at its limit? Insights into the number and evolutionary dynamics of the sex-determining specificities of the honey bee Apis mellifera.

Science.gov (United States)

Lechner, Sarah; Ferretti, Luca; Schöning, Caspar; Kinuthia, Wanja; Willemsen, David; Hasselmann, Martin

2014-02-01

Deciphering the evolutionary processes driving nucleotide variation in multiallelic genes is limited by the number of genetic systems in which such genes occur. The complementary sex determiner (csd) gene in the honey bee Apis mellifera is an informative example for studying allelic diversity and the underlying evolutionary forces in a well-described model of balancing selection. Acting as the primary signal of sex determination, diploid individuals heterozygous for csd develop into females, whereas csd homozygotes are diploid males that have zero fitness. Examining 77 of the functional heterozygous csd allele pairs, we established a combinatorical criteria that provide insights into the minimum number of amino acid differences among those pairs. Given a data set of 244 csd sequences, we show that the total number of csd alleles found in A. mellifera ranges from 53 (locally) to 87 (worldwide), which is much higher than was previously reported (20). Using a coupon-collector model, we extrapolate the presence of in total 116-145 csd alleles worldwide. The hypervariable region (HVR) is of particular importance in determining csd allele specificity, and we provide for this region evidence of high evolutionary rate for length differences exceeding those of microsatellites. The proportion of amino acids driven by positive selection and the rate of nonsynonymous substitutions in the HVR-flanking regions reach values close to 1 but differ with respect to the HVR length. Using a model of csd coalescence, we identified the high originating rate of csd specificities as a major evolutionary force, leading to an origin of a novel csd allele every 400,000 years. The csd polymorphism frequencies in natural populations indicate an excess of new mutations, whereas signs of ancestral transspecies polymorphism can still be detected. This study provides a comprehensive view of the enormous diversity and the evolutionary forces shaping a multiallelic gene.

Nucleotide Variability at Its Limit? Insights into the Number and Evolutionary Dynamics of the Sex-Determining Specificities of the Honey Bee Apis mellifera

Science.gov (United States)

Lechner, Sarah; Ferretti, Luca; Schöning, Caspar; Kinuthia, Wanja; Willemsen, David; Hasselmann, Martin

2014-01-01

Deciphering the evolutionary processes driving nucleotide variation in multiallelic genes is limited by the number of genetic systems in which such genes occur. The complementary sex determiner (csd) gene in the honey bee Apis mellifera is an informative example for studying allelic diversity and the underlying evolutionary forces in a well-described model of balancing selection. Acting as the primary signal of sex determination, diploid individuals heterozygous for csd develop into females, whereas csd homozygotes are diploid males that have zero fitness. Examining 77 of the functional heterozygous csd allele pairs, we established a combinatorical criteria that provide insights into the minimum number of amino acid differences among those pairs. Given a data set of 244 csd sequences, we show that the total number of csd alleles found in A. mellifera ranges from 53 (locally) to 87 (worldwide), which is much higher than was previously reported (20). Using a coupon-collector model, we extrapolate the presence of in total 116–145 csd alleles worldwide. The hypervariable region (HVR) is of particular importance in determining csd allele specificity, and we provide for this region evidence of high evolutionary rate for length differences exceeding those of microsatellites. The proportion of amino acids driven by positive selection and the rate of nonsynonymous substitutions in the HVR-flanking regions reach values close to 1 but differ with respect to the HVR length. Using a model of csd coalescence, we identified the high originating rate of csd specificities as a major evolutionary force, leading to an origin of a novel csd allele every 400,000 years. The csd polymorphism frequencies in natural populations indicate an excess of new mutations, whereas signs of ancestral transspecies polymorphism can still be detected. This study provides a comprehensive view of the enormous diversity and the evolutionary forces shaping a multiallelic gene. PMID:24170493

Sex Determination from Fragmented and Degenerated DNA by Amplified Product-Length Polymorphism Bidirectional SNP Analysis of Amelogenin and SRY Genes

Science.gov (United States)

Masuyama, Kotoka; Shojo, Hideki; Nakanishi, Hiroaki; Inokuchi, Shota; Adachi, Noboru

2017-01-01

Sex determination is important in archeology and anthropology for the study of past societies, cultures, and human activities. Sex determination is also one of the most important components of individual identification in criminal investigations. We developed a new method of sex determination by detecting a single-nucleotide polymorphism in the amelogenin gene using amplified product-length polymorphisms in combination with sex-determining region Y analysis. We particularly focused on the most common types of postmortem DNA damage in ancient and forensic samples: fragmentation and nucleotide modification resulting from deamination. Amplicon size was designed to be less than 60 bp to make the method more useful for analyzing degraded DNA samples. All DNA samples collected from eight Japanese individuals (four male, four female) were evaluated correctly using our method. The detection limit for accurate sex determination was determined to be 20 pg of DNA. We compared our new method with commercial short tandem repeat analysis kits using DNA samples artificially fragmented by ultraviolet irradiation. Our novel method was the most robust for highly fragmented DNA samples. To deal with allelic dropout resulting from deamination, we adopted “bidirectional analysis,” which analyzed samples from both sense and antisense strands. This new method was applied to 14 Jomon individuals (3500-year-old bone samples) whose sex had been identified morphologically. We could correctly identify the sex of 11 out of 14 individuals. These results show that our method is reliable for the sex determination of highly degenerated samples. PMID:28052096

The ecology and evolution of temperature-dependent reaction norms for sex determination in reptiles: a mechanistic conceptual model.

Science.gov (United States)

Pezaro, Nadav; Doody, J Sean; Thompson, Michael B

2017-08-01

Sex-determining mechanisms are broadly categorised as being based on either genetic or environmental factors. Vertebrate sex determination exhibits remarkable diversity but displays distinct phylogenetic patterns. While all eutherian mammals possess XY male heterogamety and female heterogamety (ZW) is ubiquitous in birds, poikilothermic vertebrates (fish, amphibians and reptiles) exhibit multiple genetic sex-determination (GSD) systems as well as environmental sex determination (ESD). Temperature is the factor controlling ESD in reptiles and temperature-dependent sex determination (TSD) in reptiles has become a focal point in the study of this phenomenon. Current patterns of climate change may cause detrimental skews in the population sex ratios of reptiles exhibiting TSD. Understanding the patterns of variation, both within and among populations and linking such patterns with the selection processes they are associated with, is the central challenge of research aimed at predicting the capacity of populations to adapt to novel conditions. Here we present a conceptual model that innovates by defining an individual reaction norm for sex determination as a range of incubation temperatures. By deconstructing individual reaction norms for TSD and revealing their underlying interacting elements, we offer a conceptual solution that explains how variation among individual reaction norms can be inferred from the pattern of population reaction norms. The model also links environmental variation with the different patterns of TSD and describes the processes from which they may arise. Specific climate scenarios are singled out as eco-evolutionary traps that may lead to demographic extinction or a transition to either male or female heterogametic GSD. We describe how the conceptual principles can be applied to interpret TSD data and to explain the adaptive capacity of TSD to climate change as well as its limits and the potential applications for conservation and management

Sex determination by tooth size in a sample of Greek population.

Science.gov (United States)

Mitsea, A G; Moraitis, K; Leon, G; Nicopoulou-Karayianni, K; Spiliopoulou, C

2014-08-01

Sex assessment from tooth measurements can be of major importance for forensic and bioarchaeological investigations, especially when only teeth or jaws are available. The purpose of this study is to assess the reliability and applicability of establishing sex identity in a sample of Greek population using the discriminant function proposed by Rösing et al. (1995). The study comprised of 172 dental casts derived from two private orthodontic clinics in Athens. The individuals were randomly selected and all had clear medical history. The mesiodistal crown diameters of all the teeth were measured apart from those of the 3rd molars. The values quoted for the sample to which the discriminant function was first applied were similar to those obtained for the Greek sample. The results of the preliminary statistical analysis did not support the use of the specific discriminant function for a reliable determination of sex by means of the mesiodistal diameter of the teeth. However, there was considerable variation between different populations and this might explain the reason for lack of discriminating power of the specific function in the Greek population. In order to investigate whether a better discriminant function could be obtained using the Greek data, separate discriminant function analysis was performed on the same teeth and a different equation emerged without, however, any real improvement in the classification process, with an overall correct classification of 72%. The results showed that there were a considerably higher percentage of females correctly classified than males. The results lead to the conclusion that the use of the mesiodistal diameter of teeth is not as a reliable method as one would have expected for determining sex of human remains from a forensic context. Therefore, this method could be used only in combination with other identification approaches. Copyright © 2014. Published by Elsevier GmbH.

Expression profiles of amhy and major sex-related genes during gonadal sex differentiation and their relation with genotypic and temperature-dependent sex determination in pejerrey Odontesthes bonariensis.

Science.gov (United States)

Zhang, Yan; Hattori, Ricardo S; Sarida, Munti; García, Estefany L; Strüssmann, Carlos Augusto; Yamamoto, Yoji

2018-03-15

To shed light on the mechanisms of and interactions of GSD and TSD in pejerrey, we investigated how the transcriptional profiles of amhy and amha are affected by feminizing (17 °C) and masculinizing (29 °C) temperatures during the critical period of sex determination/differentiation and their relation with the expression profiles of AMH receptor type II (amhrII), gonadal aromatase (cyp19a1a), and 11 beta-hydroxysteroid dehydrogenase 2 (hsd11b2). Careful consideration of the results of this study and all information currently available for this species, including similar analyzes for an intermediate, mixed-sex promoting temperature (25 °C), suggests a model for genotypic/temperature-dependent sex determination and gonadal sex differentiation that involves a) cyp19a1a-dependent, developmentally-programmed ovarian development as the default state that becomes self-sustaining in the absence of a potent and timely masculinizing stimulus, b) early, developmentally-programmed amhy expression and high temperature as masculinization signals that antagonize the putative female pathway by suppressing cyp19a1a expression, c) increasing stress response, cortisol, and the synthesis of the masculinizing androgen 11-keto-testosterone via hsd11b2 with increasing temperature that is important for masculinization in both genotypes but particularly so in XX individuals, and d) an endocrine network with positive/negative feedback mechanisms that ensure fidelity of the male/female pathway once started. The proposed model, albeit tentative and non-all inclusive, accounts for the continuum of responses, from all-females at low temperatures to all-males at high temperatures and for the balanced-, genotype-linked sex ratios obtained at intermediate temperatures, and therefore supports the coexistence of TSD and GSD in pejerrey across the range of viable temperatures for this species. Copyright © 2018 Elsevier Inc. All rights reserved.

Mutations in the testis-specific enhancer of SOX9 in the SRY independent sex-determining mechanism in the genus Tokudaia.

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Ryutaro Kimura

Full Text Available SRY (sex-determining region Y is widely conserved in eutherian mammals as a sex-determining gene located on the Y chromosome. SRY proteins bind to the testis-specific enhancer of SOX9 (TES with SF1 to upregulate SOX9 expression in undifferentiated gonads of XY embryos of humans and mice. The core region within TES, named TESCO, is an important enhancer for mammalian sex determination. We show that TESCO of the genus Tokudaia lost enhancer activity caused by mutations in its SRY and SF1 binding sites. Two species of Tokudaia do not have the Y chromosome or SRY, and one species has multiple SRYs located on the neo-Y chromosome consisting of the Y fused with an autosome. The sequence of Tokudaia TESCO exhibited more than 83% identity with mouse TESCO, however, nucleotide substitution(s were found in two out of three SRY binding sites and in five out of six SF1 binding sites. TESCO of all species showed low enhancer activity in cells co-transfected with SRY and SF1, and SOX9 and SF1 in reporter gene assays. Mutated TESCO, in which nucleotide substitutions found in SRY and SF1 binding sites were replaced with mouse sequence, recovered the activity. Furthermore, SRYs of the SRY-positive species could not activate the mutated TESCO or mouse TESCO, suggesting that SRYs lost function as a sex-determining gene any more. Our results indicate that the SRY dependent sex-determining mechanism was lost in a common ancestor of the genus Tokudaia caused by nucleotide substitutions in SRY and SF1 binding sites after emergence of a new sex-determining gene. We present the first evidence for an intermediate stage of the switchover from SRY to a new sex-determining gene in the evolution of mammalian sex-determining mechanism.

Mutations in the testis-specific enhancer of SOX9 in the SRY independent sex-determining mechanism in the genus Tokudaia.

Science.gov (United States)

Kimura, Ryutaro; Murata, Chie; Kuroki, Yoko; Kuroiwa, Asato

2014-01-01

SRY (sex-determining region Y) is widely conserved in eutherian mammals as a sex-determining gene located on the Y chromosome. SRY proteins bind to the testis-specific enhancer of SOX9 (TES) with SF1 to upregulate SOX9 expression in undifferentiated gonads of XY embryos of humans and mice. The core region within TES, named TESCO, is an important enhancer for mammalian sex determination. We show that TESCO of the genus Tokudaia lost enhancer activity caused by mutations in its SRY and SF1 binding sites. Two species of Tokudaia do not have the Y chromosome or SRY, and one species has multiple SRYs located on the neo-Y chromosome consisting of the Y fused with an autosome. The sequence of Tokudaia TESCO exhibited more than 83% identity with mouse TESCO, however, nucleotide substitution(s) were found in two out of three SRY binding sites and in five out of six SF1 binding sites. TESCO of all species showed low enhancer activity in cells co-transfected with SRY and SF1, and SOX9 and SF1 in reporter gene assays. Mutated TESCO, in which nucleotide substitutions found in SRY and SF1 binding sites were replaced with mouse sequence, recovered the activity. Furthermore, SRYs of the SRY-positive species could not activate the mutated TESCO or mouse TESCO, suggesting that SRYs lost function as a sex-determining gene any more. Our results indicate that the SRY dependent sex-determining mechanism was lost in a common ancestor of the genus Tokudaia caused by nucleotide substitutions in SRY and SF1 binding sites after emergence of a new sex-determining gene. We present the first evidence for an intermediate stage of the switchover from SRY to a new sex-determining gene in the evolution of mammalian sex-determining mechanism.

Mental disorders frequency alternative and complementary ...

African Journals Online (AJOL)

Objectives: Diabetes mellitus (DM) and hypertension (HT) are chronic disorders with which mental disorders may coexist and for which patients may resort to alternative medicine use. Alternative and complementary medicine is a treatment option that patients tend to use. This study is to determine the prevalence of mental ...

Prenatal sex determination by radioimmunoassay of testosterone with and without chromatography of the amniotic fluid

International Nuclear Information System (INIS)

Distler, W.; Boniver-Ollmann, U.; Tigges, J.; Terinde, R.; Claussen, U.

1979-01-01

Amniotic fluid testosterone measured by radioimmunoassay (RIA) without chromatography (immunoreactive testosterone) seems not to be a definitive test for prenatal sex determination in all cases. In this study testosterone (T) levels measured by RIA with chromatography of the amniotic fluid samples were compared with immunoreactive testosterone (iT) values, to determine the predictive accuracy of the two methods. In 111 amniotic fluid samples between 15 and 19 weeks of gestation iT and T were measured parallelly. There are significant differences between iT- and T-means of both sexes (p [de

Label-free detection of sex determining region Y (SRY) via capacitive biosensor

KAUST Repository

Sivashankar, Shilpa; Sapsanis, Christos; Agambayev, Sumeyra; Buttner, Ulrich; Salama, Khaled N.

2016-01-01

In this work, we present for the first time, the use of a simple fractal capacitive biosensor for the quantification and detection of sex-determining region Y (SRY) genes. This section of genetic code, which is found on the Y chromosome, finds

Mandibular ramus: A predictor for sex determination - A digital radiographic study

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Kotya Naik Maloth

2017-01-01

Full Text Available Aim: To evaluate mandibular ramus linear measurements on digital panoramic radiographs and to assess the usefulness of mandibular ramus in sex determination. Material and Methods: A retrospective study was conducted on 100 patients (50 males and 50 females using digital panoramic radiographs of Khammam population with age ranging from 20 to 50 years. Standard digital panoramic radiographs were taken without any errors by Sirona, ORTHOPHOS XG 5 machine. The following five mandibular linear measurements were performed in cm such as upper ramus breadth, lower ramus breadth, condylar ramus height, projective ramus height, and coronoid ramus height. The obtained data were analyzed with the software SPSS 13.0 for statistical analysis using discriminate methods. Results: In the present study, all the linear measurements of mandibular ramus on digital panoramic radiographs showed a statistically significant difference between the genders. Conclusion: We conclude that the use of mandibular ramus is recommended as an aid for sex determination in forensic science due to their unique feature of sexual dimorphism.

Fish with thermolabile sex determination (TSD) as models to study brain sex differentiation.

Science.gov (United States)

Blázquez, Mercedes; Somoza, Gustavo M

2010-05-01

As fish are ectothermic animals, water temperature can affect their basic biological processes such as larval development, growth and reproduction. Similar to reptiles, the incubation temperature during early phases of development is capable to modify sex ratios in a large number of fish species. This phenomenon, known as thermolabile sex determination (TSD) was first reported in Menidia menidia, a species belonging to the family Atherinopsidae. Since then, an increasing number of fish have also been found to exhibit TSD. Traditionally, likewise in reptiles, several TSD patterns have been described in fish, however it has been recently postulated that only one, females at low temperatures and males at high temperatures, may represent the "real" or "true" TSD. Many studies regarding the influence of temperature on the final sex ratios have been focused on the expression and activity of gonadal aromatase, the enzyme involved in the conversion of androgens into estrogens and encoded by the cyp19a1a gene. In this regard, teleost fish, may be due to a whole genome duplication event, produce another aromatase enzyme, commonly named brain aromatase, encoded by the cyp19a1b gene. Contrary to what has been described in other vertebrates, fish exhibit very high levels of aromatase activity in the brain and therefore they synthesize high amounts of neuroestrogens. However, its biological significance is still not understood. In addition, the mechanism whereby temperature can induce the development of a testis or an ovary still remains elusive. In this context the present review is aimed to discuss several theories about the possible role of brain aromatase using fish as models. The relevance of brain aromatase and therefore of neuroestrogens as the possible cue for gonadal differentiation is raised. In addition, the possible role of brain aromatase as the way to keep the high levels of neurogenesis in fish is also considered. Several key examples of how teleosts and aromatase

Metric Sex Determination of the Human Coxal Bone on a Virtual Sample using Decision Trees.

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Savall, Frédéric; Faruch-Bilfeld, Marie; Dedouit, Fabrice; Sans, Nicolas; Rousseau, Hervé; Rougé, Daniel; Telmon, Norbert

2015-11-01

Decision trees provide an alternative to multivariate discriminant analysis, which is still the most commonly used in anthropometric studies. Our study analyzed the metric characterization of a recent virtual sample of 113 coxal bones using decision trees for sex determination. From 17 osteometric type I landmarks, a dataset was built with five classic distances traditionally reported in the literature and six new distances selected using the two-step ratio method. A ten-fold cross-validation was performed, and a decision tree was established on two subsamples (training and test sets). The decision tree established on the training set included three nodes and its application to the test set correctly classified 92% of individuals. This percentage was similar to the data of the literature. The usefulness of decision trees has been demonstrated in numerous fields. They have been already used in sex determination, body mass prediction, and ancestry estimation. This study shows another use of decision trees enabling simple and accurate sex determination. © 2015 American Academy of Forensic Sciences.

Species identification and sex determination of the genus Nepenthes (Nepenthaceae).

Science.gov (United States)

Mokkamul, Piya; Chaveerach, Arunrat; Sudmoon, Runglawan; Tanee, Tawatchai

2007-02-15

Nepenthes species are well known for their ornamentally attractive pitchers. The species diversity was randomly surveyed in some conservation areas of Thailand and three species were found, namely N. gracilis Korth., N. mirabilis Druce. and N. smilesii Hemsl. Young plants as unknown species from Chatuchak market were added in plant sampled set. Thirty two Inter Simple Sequence Repeat (ISSR) primers were screened and 13 successful primers were used to produce DNA banding patterns for constructing a dendrogram. The dendrogram is potentially power tool to identify unknown species from Chatuchak market, differentiate species population, population by geographical areas and sex determination. The geographical area of N. mirabilis was specified to Southern and Northeastern regions and finally, subdivided into exact areas according to province. Male and female plants of N. gracilis at Phu Wua Wildlife Sanctuary and N. mirabilis at Bung Khonglong non-hunting area were determined. Two unknown species from Chatuchak market were analyzed to be N. mirabilis with the genetic similarities (S) 77.2 to 84.7. Be more sex specific in all sample studied, 37 Random Amplified Polymorphic DNA (RAPD) primers were investigated. The result shows that only one RAPD primer show high resolution results at about 750 bp specific male-related marker.

The roles of Dmrt (Double sex/Male-abnormal-3 Related Transcription factor) genes in sex determination and differentiation mechanisms: Ubiquity and diversity across the animal kingdom.

Science.gov (United States)

Picard, Marion Anne-Lise; Cosseau, Céline; Mouahid, Gabriel; Duval, David; Grunau, Christoph; Toulza, Ève; Allienne, Jean-François; Boissier, Jérôme

2015-07-01

The Dmrt (Double sex/Male-abnormal-3 Related Transcription factor) genes have been intensively studied because they represent major transcription factors in the pathways governing sex determination and differentiation. These genes have been identified in animal groups ranging from cnidarians to mammals, and some of the genes functionally studied. Here, we propose to analyze (i) the presence/absence of various Dmrt gene groups in the different taxa across the animal kingdom; (ii) the relative expression levels of the Dmrt genes in each sex; (iii) the specific spatial (by organ) and temporal (by developmental stage) variations in gene expression. This review considers non-mammalian animals at all levels of study (i.e. no particular importance is given to animal models), and using all types of sexual strategy (hermaphroditic or gonochoric) and means of sex determination (i.e. genetic or environmental). To conclude this global comparison, we offer an analysis of the DM domains conserved among the different DMRT proteins, and propose a general sex-specific pattern for each member of the Dmrt gene family. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Identifying determinants of effective complementary feeding behaviour change interventions in developing countries

Science.gov (United States)

Fabrizio, Cecilia S; van Liere, Marti; Pelto, Gretel

2014-01-01

As stunting moves to the forefront of the global agenda, there is substantial evidence that behaviour change interventions (BCI) can improve infant feeding practices and growth. However, this evidence has not been translated into improved outcomes on a national level because we do not know enough about what makes these interventions work, for whom, when, why, at what cost and for how long. Our objective was to examine the design and implementation of complementary feeding BCI, from the peer-reviewed literature, to identify generalisable key determinants. We identified 29 studies that evaluated BCI efficacy or effectiveness, were conducted in developing countries, and reported outcomes on infant and young children aged 6–24 months. Two potential determinants emerged: (1) effective studies used formative research to identify cultural barriers and enablers to optimal feeding practices, to shape the intervention strategy, and to formulate appropriate messages and mediums for delivery; (2) effective studies delineated the programme impact pathway to the target behaviour change and assessed intermediary behaviour changes to learn what worked. We found that BCI that used these developmental and implementation processes could be effective despite heterogeneous approaches and design components. Our analysis was constrained, however, by the limited published data on how design and implementation were carried out, perhaps because of publishing space limits. Information on cost-effectiveness, sustainability and scalability was also very limited. We suggest a more comprehensive reporting process and a more strategic research agenda to enable generalisable evidence to accumulate. PMID:24798264

A single sex pheromone receptor determines chemical response specificity of sexual behavior in the silkmoth Bombyx mori.

Science.gov (United States)

Sakurai, Takeshi; Mitsuno, Hidefumi; Haupt, Stephan Shuichi; Uchino, Keiro; Yokohari, Fumio; Nishioka, Takaaki; Kobayashi, Isao; Sezutsu, Hideki; Tamura, Toshiki; Kanzaki, Ryohei

2011-06-01

In insects and other animals, intraspecific communication between individuals of the opposite sex is mediated in part by chemical signals called sex pheromones. In most moth species, male moths rely heavily on species-specific sex pheromones emitted by female moths to identify and orient towards an appropriate mating partner among a large number of sympatric insect species. The silkmoth, Bombyx mori, utilizes the simplest possible pheromone system, in which a single pheromone component, (E, Z)-10,12-hexadecadienol (bombykol), is sufficient to elicit full sexual behavior. We have previously shown that the sex pheromone receptor BmOR1 mediates specific detection of bombykol in the antennae of male silkmoths. However, it is unclear whether the sex pheromone receptor is the minimally sufficient determination factor that triggers initiation of orientation behavior towards a potential mate. Using transgenic silkmoths expressing the sex pheromone receptor PxOR1 of the diamondback moth Plutella xylostella in BmOR1-expressing neurons, we show that the selectivity of the sex pheromone receptor determines the chemical response specificity of sexual behavior in the silkmoth. Bombykol receptor neurons expressing PxOR1 responded to its specific ligand, (Z)-11-hexadecenal (Z11-16:Ald), in a dose-dependent manner. Male moths expressing PxOR1 exhibited typical pheromone orientation behavior and copulation attempts in response to Z11-16:Ald and to females of P. xylostella. Transformation of the bombykol receptor neurons had no effect on their projections in the antennal lobe. These results indicate that activation of bombykol receptor neurons alone is sufficient to trigger full sexual behavior. Thus, a single gene defines behavioral selectivity in sex pheromone communication in the silkmoth. Our findings show that a single molecular determinant can not only function as a modulator of behavior but also as an all-or-nothing initiator of a complex species-specific behavioral sequence.

A single sex pheromone receptor determines chemical response specificity of sexual behavior in the silkmoth Bombyx mori.

Directory of Open Access Journals (Sweden)

Takeshi Sakurai

2011-06-01

Full Text Available In insects and other animals, intraspecific communication between individuals of the opposite sex is mediated in part by chemical signals called sex pheromones. In most moth species, male moths rely heavily on species-specific sex pheromones emitted by female moths to identify and orient towards an appropriate mating partner among a large number of sympatric insect species. The silkmoth, Bombyx mori, utilizes the simplest possible pheromone system, in which a single pheromone component, (E, Z-10,12-hexadecadienol (bombykol, is sufficient to elicit full sexual behavior. We have previously shown that the sex pheromone receptor BmOR1 mediates specific detection of bombykol in the antennae of male silkmoths. However, it is unclear whether the sex pheromone receptor is the minimally sufficient determination factor that triggers initiation of orientation behavior towards a potential mate. Using transgenic silkmoths expressing the sex pheromone receptor PxOR1 of the diamondback moth Plutella xylostella in BmOR1-expressing neurons, we show that the selectivity of the sex pheromone receptor determines the chemical response specificity of sexual behavior in the silkmoth. Bombykol receptor neurons expressing PxOR1 responded to its specific ligand, (Z-11-hexadecenal (Z11-16:Ald, in a dose-dependent manner. Male moths expressing PxOR1 exhibited typical pheromone orientation behavior and copulation attempts in response to Z11-16:Ald and to females of P. xylostella. Transformation of the bombykol receptor neurons had no effect on their projections in the antennal lobe. These results indicate that activation of bombykol receptor neurons alone is sufficient to trigger full sexual behavior. Thus, a single gene defines behavioral selectivity in sex pheromone communication in the silkmoth. Our findings show that a single molecular determinant can not only function as a modulator of behavior but also as an all-or-nothing initiator of a complex species

Sex determination in femurs of modern Egyptians: A comparative study between metric measurements and SRY gene detection

Directory of Open Access Journals (Sweden)

Iman F. Gaballah

2014-12-01

Conclusion: The SRY gene detection method for sex determination is quick and simple, requiring only one PCR reaction. It corroborates the results obtained from anatomical measurements and further confirms the sex of the femur bone in question.

Expression of putative sex-determining genes during the thermosensitive period of gonad development in the snapping turtle, Chelydra serpentina.

Science.gov (United States)

Rhen, T; Metzger, K; Schroeder, A; Woodward, R

2007-01-01

Modes of sex determination are quite variable in vertebrates. The developmental decision to form a testis or an ovary can be influenced by one gene, several genes, environmental variables, or a combination of these factors. Nevertheless, certain morphogenetic aspects of sex determination appear to be conserved in amniotes. Here we clone fragments of nine candidate sex-determining genes from the snapping turtle Chelydra serpentina, a species with temperature-dependent sex determination (TSD). We then analyze expression of these genes during the thermosensitive period of gonad development. In particular, we compare gene expression profiles in gonads from embryos incubated at a male-producing temperature to those from embryos at a female-producing temperature. Expression of Dmrt1 and Sox9 mRNA increased gradually at the male-producing temperature, but was suppressed at the female-producing temperature. This finding suggests that Dmrt1 and Sox9 play a role in testis development. In contrast, expression of aromatase, androgen receptor (Ar), and Foxl2 mRNA was constant at the male-producing temperature, but increased several-fold in embryos at the female-producing temperature. Aromatase, Ar, and Foxl2 may therefore play a role in ovary development. In addition, there was a small temperature effect on ER alpha expression with lower mRNA levels found in embryos at the female-producing temperature. Finally, Dax1, Fgf9, and SF-1 were not differentially expressed during the sex-determining period, suggesting these genes are not involved in sex determination in the snapping turtle. Comparison of gene expression profiles among amniotes indicates that Dmrt1 and Sox9 are part of a core testis-determining pathway and that Ar, aromatase, ER alpha, and Foxl2 are part of a core ovary-determining pathway. 2007 S. Karger AG, Basel

Sex determination: ciliates' self-censorship.

Science.gov (United States)

Bloomfield, Gareth

2014-07-07

Differentiation involves the expression of certain latent cellular characteristics and the repression of others. A new study has revealed how Paramecium uses short RNAs to delete information from the somatic genome of one of its two sexes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Determination of Sperm Sex Ratio in Bovine Semen Using Multiplex Real-time Polymerase Chain Reaction

Directory of Open Access Journals (Sweden)

Trisadee Khamlor

2014-10-01

Full Text Available Gender selection is important in livestock industries; for example, female calves are required in the dairy industry. Sex-sorted semen is commonly used for the production of calves of the desired gender. However, assessment of the sex ratio of the sorted semen is tedious and expensive. In this study, a rapid, cost effective and reliable method for determining the sex ratio was developed using a multiplex real-time polymerase chain reaction (PCR assay. In this assay, the X and Y chromosome-specific markers, i.e., bovine proteolipid protein (PLP gene and sex-determining region Y (SRY were simultaneously quantified in a single tube. The multiplex real-time PCR assay was shown to have high amplification efficiencies (97% to 99% comparable to the separated-tube simplex real-time PCR assay. The results obtained from both assays were not significantly different (p>0.05. The multiplex assay was validated using reference DNA of known X ratio (10%, 50%, and 90% as templates. The measured %X in semen samples were the same within 95% confidence intervals as the expected values, i.e., >90% in X-sorted semen, <10% in Y-sorted semen and close to 50% in the unsorted semen. The multiplex real-time PCR assay as shown in this study can thus be used to assess purity of sex-sorted semen.

Genetic studies on sex determination and colouration in Nile tilapia (Oreochromis niloticus L.)

International Nuclear Information System (INIS)

Karayuecel, I.

1999-05-01

The present study was undertaken to investigate colour and sex determination mechanisms through the application of androgenesis, gynogenesis and controlled breeding programme with the objective of producing all red males in O. niloticus. The highest yield of androgenetic haploid to pigmentation stage was 24.6±3.5% (relative to controls) with optimal UV irradiation dose of 450JM -2 for 5 minutes. The highest survival rate of diploid androgens was 0.07±0.07% (relative to controls) to yolk sac stage using a heat shock of 42.5 deg. C for 3 minutes 30 seconds applied at 25 minutes after fertilisation. All paternal inheritance of diploid androgenetic tilapia was verified using DNA fingerprinting. The mean recombination frequency of the red skin colour gene in meiotic gynogens was 0.12±0.04. All maternal inheritance of meiotic gynogens was verified using the isozyme locus ADA*. Analyses of sex ratios of meiotic gynogens suggested that male progenies were produced by an epistatic sex determining locus (SDL-2 with two alleles SR and sr) causing female to male sex reversal in the homozygous phase (srsr) but with limited penetrance. A close linkage was found between a sex determining locus (SDL-2) and the red gene. No significant difference was found between colour genotypes (namely homozygous red, heterozygous red and wild type) in terms of total fecundity, ISI (inter spawning interval), egg size and survival rate. Overall mean ISI was 26.3±1.0 days. Mean total fecundity was 1096 eggs. Fecundity varied over successive spawns but this variation did not appear to be related to spawning periodicity. Hormonal and thermal feminization were compared on all YY male progeny of O. niloticus. While similar female percentages of 32.0±5.2 and 33.8±1.5% were produced, significantly higher intersex percentages of 18.5±2.5 and 1.6±0.8 were observed in heat and DES treated groups, respectively. Heat treatment groups showed the lowest survival rate of 62.6±9.8% compared to the

Genetic studies on sex determination and colouration in Nile tilapia (Oreochromis niloticus L.)

Energy Technology Data Exchange (ETDEWEB)

Karayuecel, I

1999-05-01

The present study was undertaken to investigate colour and sex determination mechanisms through the application of androgenesis, gynogenesis and controlled breeding programme with the objective of producing all red males in O. niloticus. The highest yield of androgenetic haploid to pigmentation stage was 24.6{+-}3.5% (relative to controls) with optimal UV irradiation dose of 450JM{sup -2} for 5 minutes. The highest survival rate of diploid androgens was 0.07{+-}0.07% (relative to controls) to yolk sac stage using a heat shock of 42.5 deg. C for 3 minutes 30 seconds applied at 25 minutes after fertilisation. All paternal inheritance of diploid androgenetic tilapia was verified using DNA fingerprinting. The mean recombination frequency of the red skin colour gene in meiotic gynogens was 0.12{+-}0.04. All maternal inheritance of meiotic gynogens was verified using the isozyme locus ADA*. Analyses of sex ratios of meiotic gynogens suggested that male progenies were produced by an epistatic sex determining locus (SDL-2 with two alleles SR and sr) causing female to male sex reversal in the homozygous phase (srsr) but with limited penetrance. A close linkage was found between a sex determining locus (SDL-2) and the red gene. No significant difference was found between colour genotypes (namely homozygous red, heterozygous red and wild type) in terms of total fecundity, ISI (inter spawning interval), egg size and survival rate. Overall mean ISI was 26.3{+-}1.0 days. Mean total fecundity was 1096 eggs. Fecundity varied over successive spawns but this variation did not appear to be related to spawning periodicity. Hormonal and thermal feminization were compared on all YY male progeny of O. niloticus. While similar female percentages of 32.0{+-}5.2 and 33.8{+-}1.5% were produced, significantly higher intersex percentages of 18.5{+-}2.5 and 1.6{+-}0.8 were observed in heat and DES treated groups, respectively. Heat treatment groups showed the lowest survival rate of 62

Applying iPSCs for Preserving Endangered Species and Elucidating the Evolution of Mammalian Sex Determination.

Science.gov (United States)

Honda, Arata

2018-04-06

The endangered species Tokudaia osimensis has the unique chromosome constitution of 2n = 25, with an XO/XO sex chromosome configuration (2n = 25; XO). There is urgency to preserve this species and to elucidate the regulator(s) that can discriminate the males and females arising from the indistinguishable sex chromosome constitution. However, it is not realistic to examine this rare animal species by sacrificing individuals. Recently, true naïve induced pluripotent stem cells were successfully generated from a female T. osimensis, and the sexual plasticity of its germ cells was elucidated. This achievement constitutes the basis of an attractive research area, including embryonic fate determination, sex determination, and factor(s) that can replace the Y chromosome. In this essay, concrete strategies to conserve rare animal species and to reveal their specific characteristics using other compatible and abundant animals are proposed. © 2018 WILEY Periodicals, Inc.

When daughters are unwanted. Sex determination tests in India.

Science.gov (United States)

Kishwar, M

1995-01-01

Amniocentesis and ultrasound have been used for detecting fetal abnormalities, but in India they have been used for sex determination, leading to the abortion of hundreds of thousands of female fetuses. As a result, by 1991 the sex ratio had declined to 929 females per 1000 males from 972 females per 1000 males in 1901. This amounts to a deficit of almost 30 million females in the whole population. The regional prevalence of sex preferences has spread horizontally and vertically in the south and the northeast, where the ratios used to be more favorable. A ban on such prenatal diagnosis was passed in several states, but it proved to be ineffective and unenforceable. The result was only that the fees charged soared. Finally, in August 1994 the Indian Parliament enacted the Prenatal Diagnostics Techniques Act that prohibited genetic counseling centers to perform such procedures unless strict criteria were observed (age over 35 years, two or more previous abortions, exposure to drugs, infections, and mental or physical retardation). However, the emergence of a police-doctor nexus is dangerous for the well-being of any society and could lead to criminalization of the medical profession. Some doctors also rationalize this practice as a means of controlling population, because the custom continues to have children until the desired number of sons are born. In low sex ratio regions seclusion, disinheritance of women from property, low female literacy, poor health, greater incidence of domestic violence, and low employment rates are typical. The aversion to female infants is a culturally conditioned choice which materializes in the pervasive dread of daughters. Women themselves perpetuate the dread because of their own misery, low status, abuse, and the burden of the dowry. The devaluation of women is rooted in history, particularly in the northwest where constant wars favored a martial society for males (with strict purdah for females), and in addition British colonialism

Masturbation and Partnered Sex: Substitutes or Complements?

Science.gov (United States)

Regnerus, Mark; Price, Joseph; Gordon, David

2017-10-01

Drawing upon a large, recent probability sample of American adults ages 18-60 (7648 men and 8090 women), we explored the association between sexual frequency and masturbation, evaluating the evidence for whether masturbation compensates for unavailable sex, complements (or augments) existing paired sexual activity, or bears little association with it. We found evidence supporting a compensatory relationship between masturbation and sexual frequency for men, and a complementary one among women, but each association was both modest and contingent on how content participants were with their self-reported frequency of sex. Among men and women, both partnered status and their sexual contentment were more obvious predictors of masturbation than was recent frequency of sex. We conclude that both hypotheses as commonly evaluated suffer from failing to account for the pivotal role of subjective sexual contentment in predicting masturbation.

[Molecular mechanisms in sex determination: from gene regulation to pathology].

Science.gov (United States)

Ravel, C; Chantot-Bastaraud, S; Siffroi, J-P

2004-01-01

Testis determination is the complex process by which the bipotential gonad becomes a normal testis during embryo development. As a consequence, this process leads to sexual differentiation corresponding to the masculinization of both genital track and external genitalia. The whole phenomenon is under genetic control and is particularly driven by the presence of the Y chromosome and by the SRY gene, which acts as the key initiator of the early steps of testis determination. However, many other autosomal genes, present in both males and females, are expressed during testis formation in a gene activation pathway, which is far to be totally elucidated. All these genes act in a dosage-sensitive manner by which quantitative gene abnormalities, due to chromosomal deletions, duplications or mosaicism, may lead to testis determination failure and sex reversal.

Sox5 is involved in germ-cell regulation and sex determination in medaka following co-option of nested transposable elements.

Science.gov (United States)

Schartl, Manfred; Schories, Susanne; Wakamatsu, Yuko; Nagao, Yusuke; Hashimoto, Hisashi; Bertin, Chloé; Mourot, Brigitte; Schmidt, Cornelia; Wilhelm, Dagmar; Centanin, Lazaro; Guiguen, Yann; Herpin, Amaury

2018-01-29

Sex determination relies on a hierarchically structured network of genes, and is one of the most plastic processes in evolution. The evolution of sex-determining genes within a network, by neo- or sub-functionalization, also requires the regulatory landscape to be rewired to accommodate these novel gene functions. We previously showed that in medaka fish, the regulatory landscape of the master male-determining gene dmrt1bY underwent a profound rearrangement, concomitantly with acquiring a dominant position within the sex-determining network. This rewiring was brought about by the exaptation of a transposable element (TE) called Izanagi, which is co-opted to act as a silencer to turn off the dmrt1bY gene after it performed its function in sex determination. We now show that a second TE, Rex1, has been incorporated into Izanagi. The insertion of Rex1 brought in a preformed regulatory element for the transcription factor Sox5, which here functions in establishing the temporal and cell-type-specific expression pattern of dmrt1bY. Mutant analysis demonstrates the importance of Sox5 in the gonadal development of medaka, and possibly in mice, in a dmrt1bY-independent manner. Moreover, Sox5 medaka mutants have complete female-to-male sex reversal. Our work reveals an unexpected complexity in TE-mediated transcriptional rewiring, with the exaptation of a second TE into a network already rewired by a TE. We also show a dual role for Sox5 during sex determination: first, as an evolutionarily conserved regulator of germ-cell number in medaka, and second, by de novo regulation of dmrt1 transcriptional activity during primary sex determination due to exaptation of the Rex1 transposable element.

Use of complementary and alternative medicine in head and neck cancer patients.

Science.gov (United States)

Lim, C M; Ng, A; Loh, K S

2010-05-01

To determine the prevalence and profile of patients who use complementary and alternative medicine, within a cohort of head and neck cancer patients. Cross-sectional survey. Ninety-three consecutive head and neck cancer patients being followed up at the department of otolaryngology head and neck surgery were surveyed using an interviewer-administered questionnaire. The prevalence of complementary and alternative medicine use was 67.8 per cent. Patients who used complementary and alternative medicine were more likely to be female, better educated and younger, compared with non-users. A total of 82.5 per cent (52/63) perceived complementary and alternative medicine to be effective, even though they were aware of the lack of research and endorsement by their physician regarding such medicine. The use of complementary and alternative medicine by head and neck cancer patients is common, regardless of efficacy or cost. Clinicians should routinely ask patients about their use of complementary and alternative medicine, to facilitate communication and enable appropriate use of such medicine.

Use of complementary and alternative medicine by patients with arthritis.

Science.gov (United States)

Unsal, Ayla; Gözüm, Sebahat

2010-04-01

The aims of this study were to determine the prevalence of complementary and alternative medicine use in patients with arthritis, the types of complementary and alternative medicine used, pertinent socio-demographic factors associated with complementary and alternative medicine use and its perceived efficacy. Arthritis is a major health issue, and the use of complementary and alternative medicine among patients with arthritis is common. This is a descriptive cross-sectional study. Data were obtained from 250 patients with arthritis at the physiotherapy and immunology clinics Atatürk University Hospital in eastern Turkey between May-July 2005 using a questionnaire developed specifically for this study. The instrument included questions on socio-demographic information, disease specifics and complementary and alternative medicine usage. Seventy-six per cent of participants reported use of at least one form of complementary and alternative medicine in the previous year. Complementary and alternative medicine users and non-users were not significantly different in most socio-demographic characteristics including age, gender, marital status and education level with the exception of economic status. We categorised treatment into six complementary and alternative medicine categories: 62.6% of patients used thermal therapies; 41.5% used oral herbal therapies; 40.5% used hot therapies; 32.6% used externally applied (skin) therapies; 28.4% used massage and 12.6% used cold therapies. All forms of complementary and alternative medicine except thermal and oral herbal therapies were perceived as very effective by more than half of study participants. Complementary and alternative medicine therapy is widely used by patients with arthritis and has perceived beneficial effects. It is important for nurses and other health care professionals to be knowledgeable about the use of complementary and alternative medicine therapies when providing care to patients with arthritis because of

Steroid Signaling and Temperature-Dependent Sex Determination – Reviewing the Evidence for Early Action of Estrogen during Ovarian Determination in the Red-Eared Slider Turtle (Trachemys scripta elegans)

Science.gov (United States)

Ramsey, Mary; Crews, David

2009-01-01

The developmental processes underlying gonadal differentiation are conserved across vertebrates, but the triggers initiating these trajectories are extremely variable. The red-eared slider turtle (Trachemys scripta elegans) exhibits temperature-dependent sex determination (TSD), a system where incubation temperature during a temperature-sensitive period of development determines offspring sex. However, gonadal sex is sensitive to both temperature and hormones during this period – particularly estrogen. We present a model for temperature-based differences in aromatase expression as a critical step in ovarian determination. Localized estrogen production facilitates ovarian development while inhibiting male-specific gene expression. At male-producing temperatures aromatase is not upregulated, thereby allowing testis development. PMID:18992835

Maintaining continuity through a scientific revolution: a rereading of E. B. Wilson and T. H. Morgan on sex determination and Mendelism.

Science.gov (United States)

Kingsland, Sharon E

2007-09-01

A rereading of the American scientific literature on sex determination from 1902 to 1926 leads to a different understanding of the construction of the Mendelian-chromosome theory after 1910. There was significant intellectual continuity, which has not been properly appreciated, underlying this scientific "revolution." After reexamining the relationship between the ideas of key scientists, in particular Edmund B. Wilson and Thomas Hunt Morgan, I argue that, contrary to the historical literature, Wilson and Morgan did not adopt opposing views on Mendelism and sex determination. Rather, each preferred a non-Mendelian explanation of the determination of sex. Around 1910, both integrated the Mendelian and non-Mendelian theories to create a synthetic theory. One problem was the need to avoid an overly deterministic view of sex while also accepting the validity of Mendelism. Morgan's discovery of mutations on the X chromosome takes on different significance when set in the context of the debate about sex determination, and Calvin Bridges's work on sex determination is better seen as a development of Morgan's ideas, rather than a departure from them. Conclusions point to the role of synthesis within fields as a way to advance scientific theories and reflect on the relationship between synthesis and explanatory "pluralism" in biology.

DEHP exposure in utero disturbs sex determination and is potentially linked with precocious puberty in female mice

International Nuclear Information System (INIS)

Wang, Yongan; Yang, Qing; Liu, Wei; Yu, Mingxi; Zhang, Zhou; Cui, Xiaoyu

2016-01-01

Human's ubiquitous exposure to di (2-ethylhexyl) phthalate (DEHP) is thought to be associated with female reproductive toxicity. Previous studies found that DEHP inhibited follicle growth and decreased estradiol levels in adult female mice. However, limited information is available on the link between in utero DEHP exposure and ovarian development in female mouse offspring. The present study evaluates the disturbances in regulatory genes involved in female sex determination and the ovarian outcomes in fetal and postnatal female mice treated with in utero DEHP exposure. Pregnant mice were exposed to DEHP by gavage, with the dosage regime beginning at human relevant exposure levels. After in utero DEHP exposure, increased follicular atresia was observed in the female pups at postnatal days (PND) 21. Foxl2 expression was significantly upregulated, and Fst was significantly downregulated by DEHP above 2 mg/kg/d at PND 1 and 21. This suggests that lesion of granulosa cell differentiation and disturbance of follicle development in postnatal female mice. The expression of Cyp11a1 and Star were significantly downregulated by in utero DEHP exposure, indicating effects on estradiol biosynthesis. The female sex determination pathway was disturbed in fetus by DEHP at 2 mg/kg/d and above during the critical time window of sex determination causing significant upregulation of Foxl2, Wnt4, β-catenin and Fst. Furthermore, the increased expression of Wnt4 was supported by whole-mount in situ hybridization (WISH). These results suggest a possible association between in utero DEHP exposure and precocious puberty in the postnatal life of mice offspring, where disturbance of the sex determination regulating pathway acted as an important mechanism. - Highlights: • Maternal exposure to di (2-ethylhexyl) phthalate disturbs fetus sex determination. • DEHP upregulated Foxl2 expression potentially disturbs postnatal granulosa cell differentiation. • DEHP accelerated medulla

DEHP exposure in utero disturbs sex determination and is potentially linked with precocious puberty in female mice

Energy Technology Data Exchange (ETDEWEB)

Wang, Yongan [Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, Liaoning 116024 (China); Yang, Qing [School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning 116024 (China); Liu, Wei, E-mail: liu_wei@dlut.edu.cn [Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, Liaoning 116024 (China); Yu, Mingxi; Zhang, Zhou; Cui, Xiaoyu [Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian, Liaoning 116024 (China)

2016-09-15

Human's ubiquitous exposure to di (2-ethylhexyl) phthalate (DEHP) is thought to be associated with female reproductive toxicity. Previous studies found that DEHP inhibited follicle growth and decreased estradiol levels in adult female mice. However, limited information is available on the link between in utero DEHP exposure and ovarian development in female mouse offspring. The present study evaluates the disturbances in regulatory genes involved in female sex determination and the ovarian outcomes in fetal and postnatal female mice treated with in utero DEHP exposure. Pregnant mice were exposed to DEHP by gavage, with the dosage regime beginning at human relevant exposure levels. After in utero DEHP exposure, increased follicular atresia was observed in the female pups at postnatal days (PND) 21. Foxl2 expression was significantly upregulated, and Fst was significantly downregulated by DEHP above 2 mg/kg/d at PND 1 and 21. This suggests that lesion of granulosa cell differentiation and disturbance of follicle development in postnatal female mice. The expression of Cyp11a1 and Star were significantly downregulated by in utero DEHP exposure, indicating effects on estradiol biosynthesis. The female sex determination pathway was disturbed in fetus by DEHP at 2 mg/kg/d and above during the critical time window of sex determination causing significant upregulation of Foxl2, Wnt4, β-catenin and Fst. Furthermore, the increased expression of Wnt4 was supported by whole-mount in situ hybridization (WISH). These results suggest a possible association between in utero DEHP exposure and precocious puberty in the postnatal life of mice offspring, where disturbance of the sex determination regulating pathway acted as an important mechanism. - Highlights: • Maternal exposure to di (2-ethylhexyl) phthalate disturbs fetus sex determination. • DEHP upregulated Foxl2 expression potentially disturbs postnatal granulosa cell differentiation. • DEHP accelerated medulla

Genes involved in sex determination and the influence of ...

African Journals Online (AJOL)

As the sex reversal is a highly desired process in fish farming aiming at obtaining male mono-sexual populations (due to weight gain of males), several techniques based on direct and indirect manipulation of phenotypic sex are being tested. Recent surveys show the use of temperature as alternative to the process of sex ...

GLOBAL EPIDEMIOLOGY OF HIV AMONG FEMALE SEX WORKERS: INFLUENCE OF STRUCTURAL DETERMINANTS

Science.gov (United States)

Shannon, K; Strathdee, SA; Goldenberg, SM; Duff, P; Mwangi, P; Rusakova, M; Reza-Paul, S; Lau, J; Deering, K; Pickles, M; Boily, M-C

2014-01-01

SUMMARY Female sex workers (FSWs) bear a disproportionately large burden of HIV infection worldwide. Despite decades of research and programme activity, the epidemiology of HIV and the role that structural determinants have in mitigating or potentiating HIV epidemics and access to care for FSWs is poorly understood. We reviewed available published data for HIV prevalence and incidence, condom use, and structural determinants among this group. Only 87 (43%) of 204 unique studies reviewed explicitly examined structural determinants of HIV. Most studies were from Asia, with few from areas with a heavy burden of HIV such as sub-Saharan Africa, Russia, and eastern Europe. To further explore the potential effect of structural determinants on the course of epidemics, we used a deterministic transmission model to simulate potential HIV infections averted through structural changes in regions with concentrated and generalised epidemics, and high HIV prevalence among FSWs. This modelling suggested that elimination of sexual violence alone could avert 17% of HIV infections in Kenya (95% uncertainty interval [UI] 1–31) and 20% in Canada (95% UI 3–39) through its immediate and sustained effect on non-condom use) among FSWs and their clients in the next decade. In Kenya, scaling up of access to antiretroviral therapy among FSWs and their clients to meet WHO eligibility of a CD4 cell count of less than 500 cells per μL could avert 34% (95% UI 25–42) of infections and even modest coverage of sex worker-led outreach could avert 20% (95% UI 8–36) of infections in the next decade. Decriminalisation of sex work would have the greatest effect on the course of HIV epidemics across all settings, averting 33–46% of HIV infections in the next decade. Multipronged structural and community-led interventions are crucial to increase access to prevention and treatment and to promote human rights for FSWs worldwide. PMID:25059947

Complementary and Integrative Medicine

Science.gov (United States)

... medical treatments that are not part of mainstream medicine. When you are using these types of care, it may be called complementary, integrative, or alternative medicine. Complementary medicine is used together with mainstream medical ...

Sex determination using humeral dimensions in a sample from KwaZulu-Natal: an osteometric study.

Science.gov (United States)

Ogedengbe, Oluwatosin Olalekan; Ajayi, Sunday Adelaja; Komolafe, Omobola Aderibigbe; Zaw, Aung Khaing; Naidu, Edwin Coleridge Stephen; Okpara Azu, Onyemaechi

2017-09-01

The morphological characteristics of the humeral bone has been investigated in recent times with studies showing varying degrees of sexual dimorphism. Osteologists and forensic scientists have shown that sex determination methods based on skeletal measurements are population specific, and these population-specific variations are present in many body dimensions. The present study aims to establish sex identification using osteometric standards for the humerus in a contemporary KwaZulu-Natal population. A total of 11 parameters were measured in a sample of n=211 humeri (males, 113; females, 98) from the osteological collection in the Discipline of Clinical Anatomy, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa. The difference in means for nearly all variables were found to be significantly higher in males compared to females ( P <0.01) with the most effective single parameter for predicting sex being the vertical head diameter having an accuracy of 82.5%. Stepwise discriminant analysis increased the overall accuracy rate to 87.7% when all measurements were jointly applied. We conclude that the humerus is an important bone which can be reliably used for sex determination based on standard metric methods despite minor tribal or ancestral differences amongst an otherwise homogenous population.

Inheritance of nesting behaviour across natural environmental variation in a turtle with temperature-dependent sex determination.

Science.gov (United States)

McGaugh, Suzanne E; Schwanz, Lisa E; Bowden, Rachel M; Gonzalez, Julie E; Janzen, Fredric J

2010-04-22

Nesting behaviour is critical for reproductive success in oviparous organisms with no parental care. In organisms where sex is determined by incubation temperature, nesting behaviour may be a prime target of selection in response to unbalanced sex ratios. To produce an evolutionary change in response to sex-ratio selection, components of nesting behaviour must be heritable. We estimated the field heritability of two key components of nesting behaviour in a population of painted turtles (Chrysemys picta) with temperature-dependent sex determination by applying the 'animal model' to a pedigree reconstructed from genotype data. We obtained estimates of low to non-detectable heritability using repeated records across all environments. We then determined environment-specific heritability by grouping records with similar temperatures for the winter preceding the nesting season, a variable known to be highly associated with our two traits of interest, nest vegetation cover and Julian date of nesting. The heritability estimates of nest vegetation cover and Julian date of nesting were qualitatively highest and significant, or nearly so, after hot winters. Additive genetic variance for these traits was not detectable after cold winters. Our analysis suggests that the potential for evolutionary change of nesting behaviour may be dependent on the thermal conditions of the preceding winter, a season that is predicted to be especially subject to climate change.

Charactering the ZFAND3 gene mapped in the sex-determining locus in hybrid tilapia (Oreochromis spp.)

Science.gov (United States)

Ma, Keyi; Liao, Minghui; Liu, Feng; Ye, Baoqing; Sun, Fei; Yue, Gen Hua

2016-01-01

Zinc finger AN1-type domain 3 (ZFAND3) is essential for spermatogenesis in mice. However, its function in teleosts remains unclear. In this study, we characterized the ZFAND3 gene (termed as OsZFAND3) in an important food fish, tilapia. The OsZFAND3 cDNA sequence is 1,050 bp in length, containing an ORF of 615 bp, which encodes a putative peptide of 204 amino acid residues. Quantitative real-time PCR revealed that the OsZFAND3 transcripts were exclusively expressed in the testis and ovary. In situ hybridization showed that the high expression of OsZFAND3 transcripts was predominantly localized in the spermatocyte and spermatid. These results suggest that OsZFAND3 is involved in male germ cell maturation. Three single nucleotide polymorphisms (SNPs) were detected in the introns of OsZFAND3. The OsZFAND3 gene was mapped in the sex-determining locus on linkage group 1 (LG1). The three SNPs in the OsZFAND3 gene were strictly associated with sex phenotype, suggesting that the OsZFAND3 gene is tightly linked to the sex-determining locus. Our study provides new insights into the functions of the OsZFAND3 gene in tilapia and a foundation for further detailed analysis of the OsZFAND3 gene in sex determination and differentiation. PMID:27137111

Sex-specific genetic determinants for arterial stiffness in Dahl salt-sensitive hypertensive rats.

Science.gov (United States)

Decano, Julius L; Pasion, Khristine A; Black, Nicole; Giordano, Nicholas J; Herrera, Victoria L; Ruiz-Opazo, Nelson

2016-01-11

Arterial stiffness is an independent predictor of cardiovascular outcomes in hypertensive patients including myocardial infarction, fatal stroke, cerebral micro-bleeds which predicts cerebral hemorrhage in hypertensive patients, as well as progression to hypertension in non-hypertensive subjects. The association between arterial stiffness and various cardiovascular outcomes (coronary heart disease, stroke) remains after adjusting for age, sex, blood pressure, body mass index and other known predictors of cardiovascular disease, suggesting that arterial stiffness, measured via carotid-femoral pulse wave velocity, has a better predictive value than each of these factors. Recent evidence shows that arterial stiffening precedes the onset of high blood pressure; however their molecular genetic relationship (s) and sex-specific determinants remain uncertain. We investigated whether distinct or shared genetic determinants might underlie susceptibility to arterial stiffening in male and female Dahl salt-sensitive rats. Thus, we performed a genome-wide scan for quantitative trait loci (QTLs) affecting arterial stiffness in six-week old F2 (Dahl S x R)-intercross male and female rats characterized for abdominal aortic pulse wave velocity and aortic strain by high-resolution ultrasonography. We detected five highly significant QTLs affecting aortic stiffness: two interacting QTLs (AS-m1 on chromosome 4 and AS-m2 on chromosome16, LOD 8.8) in males and two distinct interacting QTLs (AS-f1 on chromosome 9 and AS-f2 on chromosome11, LOD 8.9) in females affecting pulse wave velocity. One QTL (AS-1 on chromosome 3, LOD 4.3) was found to influence aortic strain in a sex-independent manner. None of these arterial stiffness QTLs co-localized with previously reported blood pressure QTLs detected in equivalent genetic intercrosses. These data reveal sex-specific genetic determinants for aortic pulse wave velocity and suggest distinct polygenic susceptibility for arterial stiffness and

Molecular Sex Determination of Captive Komodo Dragons (Varanus komodoensis at Gembira Loka Zoo, Surabaya Zoo, and Ragunan Zoo, Indonesia

Directory of Open Access Journals (Sweden)

SRI SULANDARI

2014-06-01

Full Text Available Captive breeding of endangered species is often difficult, and may be hampered by many factors. Sexual monomorphism, in which males and females are not easily distinguishable, is one such factor and is a common problem in captive breeding of many avian and reptile species. Species-specific nuclear DNA markers, recently developed to identify portions of sex chromosomes, were employed in this study for sex determination of Komodo dragons (Varanus Komodoensis. Each animal was uniquely tagged using a passive integrated micro-transponder (TROVAN 100A type transponders of 13 mm in length and 2 mm in diameter. The sex of a total of 81 individual Komodo dragons (44 samples from Ragunan zoo, 26 samples from Surabaya zoo, and 11 samples from Gembira Loka zoo were determined using primers Ksex 1for and Ksex 3rev. A series of preliminary PCR amplifications were conducted using DNA from individuals of known sex. During these preliminary tests, researchers varied the annealing temperatures, number of cycles, and concentrations of reagents, in order to identify the best protocol for sex determination using our sample set. We thus developed our own PCR protocol for this study, which resulted in the amplification of band A in females and band C in males. Results from band B, however, turned out to be non-determinative in our study because, for females, band B was not always visible, and for males sometimes a similar, but lighter band was also amplified, making interpretation difficult. In this study, sex determination was based mainly on the difference in size between the female-specific 812 bp fragment and the homologous, longer fragment amplified for males.

Complementary and alternative medicine use in children with cystic fibrosis.

Science.gov (United States)

Giangioppo, Sandra; Kalaci, Odion; Radhakrishnan, Arun; Fleischer, Erin; Itterman, Jennifer; Lyttle, Brian; Price, April; Radhakrishnan, Dhenuka

2016-11-01

To estimate the overall prevalence of complementary and alternative medicine use among children with cystic fibrosis, determine specific modalities used, predictors of use and subjective helpfulness or harm from individual modalities. Of 53 children attending the cystic fibrosis clinic in London, Ontario (100% recruitment), 79% had used complementary and alternative medicine. The most commonly used modalities were air purifiers, humidifiers, probiotics, and omega-3 fatty acids. Family complementary and alternative medicine use was the only independent predictor of overall use. The majority of patients perceived benefit from specific modalities for cystic fibrosis symptoms. Given the high frequency and number of modalities used and lack of patient and disease characteristics predicting use, we recommend that health care providers should routinely ask about complementary and alternative medicine among all pediatric cystic fibrosis patients and assist patients in understanding the potential benefits and risks to make informed decisions about its use. Copyright © 2016 Elsevier Ltd. All rights reserved.

Special Section: Complementary and Alternative Medicine (CAM):Quiz on Complementary and Alternative Medicine

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... Special Section CAM Quiz on Complementary and Alternative Medicine Past Issues / Winter 2009 Table of Contents For ... low back pain. True False Complementary and alternative medicine (CAM) includes: Meditation Chiropractic Use of natural products, ...

Complementary and Alternative Medicine

Science.gov (United States)

... for Educators Search English Español Complementary and Alternative Medicine KidsHealth / For Teens / Complementary and Alternative Medicine What's ... a replacement. How Is CAM Different From Conventional Medicine? Conventional medicine is based on scientific knowledge of ...

Nutrient content and acceptability of soybean based complementary ...

African Journals Online (AJOL)

Nutrient content and acceptability of soybean based complementary food. ... African Journal of Food, Agriculture, Nutrition and Development ... A study was carried out in Morogoro region, Tanzania, to determine composition and acceptability of soy-based formulations with banana and cowpeas as traditional staples.

Vasopressin and oxytocin receptor systems in the brain: Sex differences and sex-specific regulation of social behavior.

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Dumais, Kelly M; Veenema, Alexa H

2016-01-01

The neuropeptides vasopressin (VP) and oxytocin (OT) and their receptors in the brain are involved in the regulation of various social behaviors and have emerged as drug targets for the treatment of social dysfunction in several sex-biased neuropsychiatric disorders. Sex differences in the VP and OT systems may therefore be implicated in sex-specific regulation of healthy as well as impaired social behaviors. We begin this review by highlighting the sex differences, or lack of sex differences, in VP and OT synthesis in the brain. We then discuss the evidence showing the presence or absence of sex differences in VP and OT receptors in rodents and humans, as well as showing new data of sexually dimorphic V1a receptor binding in the rat brain. Importantly, we find that there is lack of comprehensive analysis of sex differences in these systems in common laboratory species, and we find that, when sex differences are present, they are highly brain region- and species-specific. Interestingly, VP system parameters (VP and V1aR) are typically higher in males, while sex differences in the OT system are not always in the same direction, often showing higher OT expression in females, but higher OT receptor expression in males. Furthermore, VP and OT receptor systems show distinct and largely non-overlapping expression in the rodent brain, which may cause these receptors to have either complementary or opposing functional roles in the sex-specific regulation of social behavior. Though still in need of further research, we close by discussing how manipulations of the VP and OT systems have given important insights into the involvement of these neuropeptide systems in the sex-specific regulation of social behavior in rodents and humans. Copyright © 2015 Elsevier Inc. All rights reserved.

Vasopressin and oxytocin receptor systems in the brain: sex differences and sex-specific regulation of social behavior

Science.gov (United States)

Dumais, Kelly M.; Veenema, Alexa H.

2015-01-01

The neuropeptides vasopressin (VP) and oxytocin (OT) and their receptors in the brain are involved in the regulation of various social behaviors and have emerged as drug targets for the treatment of social dysfunction in several sex-biased neuropsychiatric disorders. Sex differences in the VP and OT systems may therefore be implicated in sex-specific regulation of healthy as well as impaired social behaviors. We begin this review by highlighting the sex differences, or lack of sex differences, in VP and OT synthesis in the brain. We then discuss the evidence showing the presence or absence of sex differences in VP and OT receptors in rodents and humans, as well as showing new data of sexually dimorphic V1a receptor binding in the rat brain. Importantly, we find that there is lack of comprehensive analysis of sex differences in these systems in common laboratory species, and we find that, when sex differences are present, they are highly brain region- and species- specific. Interestingly, VP system parameters (VP and V1aR) are typically higher in males, while sex differences in the OT system are not always in the same direction, often showing higher OT expression in females, but higher OT receptor expression in males. Furthermore, VP and OT receptor systems show distinct and largely non-overlapping expression in the rodent brain, which may cause these receptors to have either complementary or opposing functional roles in the sex-specific regulation of social behavior. Though still in need of further research, we close by discussing how manipulations of the VP and OT systems have given important insights into the involvement of these neuropeptide systems in the sex-specific regulation of social behavior in rodents and humans. PMID:25951955

MPK-1 ERK controls membrane organization in C. elegans oogenesis via a sex-determination module.

Science.gov (United States)

Arur, Swathi; Ohmachi, Mitsue; Berkseth, Matt; Nayak, Sudhir; Hansen, David; Zarkower, David; Schedl, Tim

2011-05-17

Tissues that generate specialized cell types in a production line must coordinate developmental mechanisms with physiological demand, although how this occurs is largely unknown. In the Caenorhabditis elegans hermaphrodite, the developmental sex-determination cascade specifies gamete sex in the distal germline, while physiological sperm signaling activates MPK-1/ERK in the proximal germline to control plasma membrane biogenesis and organization during oogenesis. We discovered repeated utilization of a self-contained negative regulatory module, consisting of NOS-3 translational repressor, FEM-CUL-2 (E3 ubiquitin ligase), and TRA-1 (Gli transcriptional repressor), which acts both in sex determination and in physiological demand control of oogenesis, coordinating these processes. In the distal germline, where MPK-1 is not activated, TRA-1 represses the male fate as NOS-3 functions in translational repression leading to inactivation of the FEM-CUL-2 ubiquitin ligase. In the proximal germline, sperm-dependent physiological MPK-1 activation results in phosphorylation-based inactivation of NOS-3, FEM-CUL-2-mediated degradation of TRA-1 and the promotion of membrane organization during oogenesis. Copyright © 2011 Elsevier Inc. All rights reserved.

Evolutionary Significance of Wolbachia-to-Animal Horizontal Gene Transfer: Female Sex Determination and the f Element in the Isopod Armadillidium vulgare.

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Cordaux, Richard; Gilbert, Clément

2017-07-21

An increasing number of horizontal gene transfer (HGT) events from bacteria to animals have been reported in the past years, many of which involve Wolbachia bacterial endosymbionts and their invertebrate hosts. Most transferred Wolbachia genes are neutrally-evolving fossils embedded in host genomes. A remarkable case of Wolbachia HGT for which a clear evolutionary significance has been demonstrated is the " f element", a nuclear Wolbachia insert involved in female sex determination in the terrestrial isopod Armadillidium vulgare . The f element represents an instance of bacteria-to-animal HGT that has occurred so recently that it was possible to infer the donor (feminizing Wolbachia closely related to the w VulC Wolbachia strain of A. vulgare ) and the mechanism of integration (a nearly complete genome inserted by micro-homology-mediated recombination). In this review, we summarize our current knowledge of the f element and discuss arising perspectives regarding female sex determination, unstable inheritance, population dynamics and the molecular evolution of the f element. Overall, the f element unifies three major areas in evolutionary biology: symbiosis, HGT and sex determination. Its characterization highlights the tremendous impact sex ratio distorters can have on the evolution of sex determination mechanisms and sex chromosomes in animals and plants.

Evolutionary Significance of Wolbachia-to-Animal Horizontal Gene Transfer: Female Sex Determination and the f Element in the Isopod Armadillidium vulgare

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Richard Cordaux

2017-07-01

Full Text Available An increasing number of horizontal gene transfer (HGT events from bacteria to animals have been reported in the past years, many of which involve Wolbachia bacterial endosymbionts and their invertebrate hosts. Most transferred Wolbachia genes are neutrally-evolving fossils embedded in host genomes. A remarkable case of Wolbachia HGT for which a clear evolutionary significance has been demonstrated is the “f element”, a nuclear Wolbachia insert involved in female sex determination in the terrestrial isopod Armadillidium vulgare. The f element represents an instance of bacteria-to-animal HGT that has occurred so recently that it was possible to infer the donor (feminizing Wolbachia closely related to the wVulC Wolbachia strain of A. vulgare and the mechanism of integration (a nearly complete genome inserted by micro-homology-mediated recombination. In this review, we summarize our current knowledge of the f element and discuss arising perspectives regarding female sex determination, unstable inheritance, population dynamics and the molecular evolution of the f element. Overall, the f element unifies three major areas in evolutionary biology: symbiosis, HGT and sex determination. Its characterization highlights the tremendous impact sex ratio distorters can have on the evolution of sex determination mechanisms and sex chromosomes in animals and plants.

Complementary and alternative therapies for low back pain

NARCIS (Netherlands)

van Tulder, M.; Furlan, A.D.; Gagnier, J.J.

2005-01-01

The support for the principles of evidence-based medicine has increased within the field of complementary and alternative medicine (CAM). The objective of this chapter is to determine the effectiveness of CAM therapies compared to placebo, no intervention, or other interventions for acute/subacute

Determining sex ratios of turtle hatchlings

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National Oceanic and Atmospheric Administration, Department of Commerce — Previous status assessments of marine turtles have assumed that the natural sex ratio of a marine turtle population is 1:1 (e.g. Conant et al. 2009). However, this...

Policing practices as a structural determinant for HIV among sex workers: a systematic review of empirical findings.

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Footer, Katherine Ha; Silberzahn, Bradley E; Tormohlen, Kayla N; Sherman, Susan G

2016-01-01

Sex workers are disproportionately infected with HIV worldwide. Significant focus has been placed on understanding the structural determinants of HIV and designing related interventions. Although there is growing international evidence that policing is an important structural HIV determinant among sex workers, the evidence has not been systematically reviewed. We conducted a systematic review of quantitative studies to examine the effects of policing on HIV and STI infection and HIV-related outcomes (condom use; syringe use; number of clients; HIV/STI testing and access) among cis and trans women sex workers. Databases included PubMed, Embase, Scopus, Sociological Abstracts, Popline, Global Health (OVID), Web of Science, IBSS, IndMed and WHOLIS. We searched for studies that included police practices as an exposure for HIV or STI infection or HIV-related outcomes. Of the 137 peer-reviewed articles identified for full text review, 14 were included, representing sex workers' experiences with police across five settings. Arrest was the most commonly explored measure with between 6 and 45% of sex workers reporting having ever been arrested. Sexual coercion was observed between 3 and 37% of the time and police extortion between 12 and 28% across studies. Half the studies used a single measure to capture police behaviours. Studies predominantly focused on "extra-legal policing practices," with insufficient attention to the role of "legal enforcement activities". All studies found an association between police behaviours and HIV or STI infection, or a related risk behaviour. The review points to a small body of evidence that confirms policing practices as an important structural HIV determinant for sex workers, but studies lack generalizability with respect to identifying those police behaviours most relevant to women's HIV risk environment.

HIV INFECTION AMONG FEMALE SEX WORKERS IN CONCENTRATED AND HIGH PREVALENCE EPIDEMICS: WHY A STRUCTURAL DETERMINANTS FRAMEWORK IS NEEDED

Science.gov (United States)

Shannon, Kate; Goldenberg, Shira M.; Deering, Kathleen N.; Strathdee, Steffanie A.

2014-01-01

Purpose of review This article reviews the current state of the epidemiological literature on female sex work and HIV from the past 18 months. We offer a conceptual framework for structural HIV determinants and sex work that unpacks intersecting structural, interpersonal, and individual biological and behavioural factors. Recent findings Our review suggests that despite the heavy HIV burden among female sex workers (FSWs) globally, data on the structural determinants shaping HIV transmission dynamics have only begun to emerge. Emerging research suggests that factors operating at macrostructural (e.g., migration, stigma, criminalized laws), community organization (e.g., empowerment) and work environment levels (e.g., violence, policing, access to condoms HIV testing, HAART) act dynamically with interpersonal (e.g., dyad factors, sexual networks) and individual biological and behavioural factors to confer risks or protections for HIV transmission in female sex work. Summary Future research should be guided by a Structural HIV Determinants Framework to better elucidate the complex and iterative effects of structural determinants with interpersonal and individual biological and behavioural factors on HIV transmission pathways among FSWs, and meet critical gaps in optimal access to HIV prevention, treatment, and care for FSWs globally. PMID:24464089

Sex identification of Nigerian indigenous chicks using Auto-sexing ...

African Journals Online (AJOL)

Sexing has been a challenging task in Nigerian indigenous chickens due to the monomorphism of chicks which makes it impossible to distinguish the male from the female until eight weeks. . Therefore, this study was carried out to determine the sex of Nigerian indigenous chicks using the common auto-sexing methods.

Self-complementary circular codes in coding theory.

Science.gov (United States)

Fimmel, Elena; Michel, Christian J; Starman, Martin; Strüngmann, Lutz

2018-04-01

Self-complementary circular codes are involved in pairing genetic processes. A maximal [Formula: see text] self-complementary circular code X of trinucleotides was identified in genes of bacteria, archaea, eukaryotes, plasmids and viruses (Michel in Life 7(20):1-16 2017, J Theor Biol 380:156-177, 2015; Arquès and Michel in J Theor Biol 182:45-58 1996). In this paper, self-complementary circular codes are investigated using the graph theory approach recently formulated in Fimmel et al. (Philos Trans R Soc A 374:20150058, 2016). A directed graph [Formula: see text] associated with any code X mirrors the properties of the code. In the present paper, we demonstrate a necessary condition for the self-complementarity of an arbitrary code X in terms of the graph theory. The same condition has been proven to be sufficient for codes which are circular and of large size [Formula: see text] trinucleotides, in particular for maximal circular codes ([Formula: see text] trinucleotides). For codes of small-size [Formula: see text] trinucleotides, some very rare counterexamples have been constructed. Furthermore, the length and the structure of the longest paths in the graphs associated with the self-complementary circular codes are investigated. It has been proven that the longest paths in such graphs determine the reading frame for the self-complementary circular codes. By applying this result, the reading frame in any arbitrary sequence of trinucleotides is retrieved after at most 15 nucleotides, i.e., 5 consecutive trinucleotides, from the circular code X identified in genes. Thus, an X motif of a length of at least 15 nucleotides in an arbitrary sequence of trinucleotides (not necessarily all of them belonging to X) uniquely defines the reading (correct) frame, an important criterion for analyzing the X motifs in genes in the future.

The role of Fanconi anemia/BRCA genes in zebrafish sex determination.

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Rodríguez-Marí, Adriana; Postlethwait, John H

2011-01-01

Fanconi anemia (FA) is a human disease of bone marrow failure, leukemia, squamous cell carcinoma, and developmental anomalies, including hypogonadism and infertility. Bone marrow transplants improve hematopoietic phenotypes but do not prevent other cancers. FA arises from mutation in any of the 15 FANC genes that cooperate to repair double stranded DNA breaks by homologous recombination. Zebrafish has a single ortholog of each human FANC gene and unexpectedly, mutations in at least two of them (fancl and fancd1(brca2)) lead to female-to-male sex reversal. Investigations show that, as in human, zebrafish fanc genes are required for genome stability and for suppressing apoptosis in tissue culture cells, in embryos treated with DNA damaging agents, and in meiotic germ cells. The sex reversal phenotype requires the action of Tp53 (p53), an activator of apoptosis. These results suggest that in normal sex determination, zebrafish oocytes passing through meiosis signal the gonadal soma to maintain expression of aromatase, an enzyme that converts androgen to estrogen, thereby feminizing the gonad and the individual. According to this model, normal male and female zebrafish differ in genetic factors that control the strength of the late meiotic oocyte-derived signal, probably by regulating the number of meiotic oocytes, which environmental factors can also alter. Transcripts from fancd1(brca2) localize at the animal pole of the zebrafish oocyte cytoplasm and are required for normal oocyte nuclear architecture, for normal embryonic development, and for preventing ovarian tumors. Embryonic DNA repair and sex reversal phenotypes provide assays for the screening of small molecule libraries for therapeutic substances for FA. Copyright © 2011 Elsevier Inc. All rights reserved.

Transmuted Complementary Weibull Geometric Distribution

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Ahmed Z. A…fify

2014-12-01

Full Text Available This paper provides a new generalization of the complementary Weibull geometric distribution that introduced by Tojeiro et al. (2014, using the quadratic rank transmutation map studied by Shaw and Buckley (2007. The new distribution is referred to as transmuted complementary Weibull geometric distribution (TCWGD. The TCWG distribution includes as special cases the complementary Weibull geometric distribution (CWGD, complementary exponential geometric distribution(CEGD,Weibull distribution (WD and exponential distribution (ED. Various structural properties of the new distribution including moments, quantiles, moment generating function and RØnyi entropy of the subject distribution are derived. We proposed the method of maximum likelihood for estimating the model parameters and obtain the observed information matrix. A real data set are used to compare the ‡exibility of the transmuted version versus the complementary Weibull geometric distribution.

Complementary and alternative medicine use in Iranian patients with diabetes mellitus.

Science.gov (United States)

Hashempur, Mohammad Hashem; Heydari, Mojtaba; Mosavat, Seyed Hamdollah; Heydari, Seyyed Taghi; Shams, Mesbah

2015-09-01

There is increasing interest in complementary and alternative medicine generally, and especially by those affected by chronic diseases, such as diabetes mellitus. We aimed to determine the prevalence and pattern of complementary and alternative medicine use among patients suffering from diabetes mellitus in Shiraz, southern Iran. Another objective was to explore associated factors for use of complementary and alternative medicine among patients with diabetes mellitus. A 19-item semi-structured questionnaire (open- and close-ended) was administered to 239 patients with diabetes mellitus in this cross-sectional study. It was carried out in two outpatient diabetes clinics affiliated with the Shiraz University of Medical Sciences, Shiraz, Iran. One hundred and eighty patients (75.3%) used at least one type of complementary and alternative medicine in the last year prior to the interview. Patients with diabetes mellitus who were living in a large family (≥5 members), not taking insulin, and believed that complementary and alternative medicine have synergistic effects with conventional medicine, were independently and significantly (P values: 0.02, 0.04, and 0.01, respectively) more likely to use complementary and alternative medicine. Most of the users (97.7%) reported use of herbal preparations, and 89.4% of users did not change their medication, neither in medication schedule nor its dosage. The use of complementary and alternative medicine, especially herbal remedies, is popular among diabetes patients in Shiraz, Iran. This use is associated with patients' family size, type of conventional medications and their view about concomitant use of complementary and conventional medicine.

Establishment and evaluation of sex determination method from 12 th thoracic vertebrae based on three-dimensional reconstructed models

International Nuclear Information System (INIS)

Guo Ming; Hou Weibin; Jing Yue; Li Youqiong; Zhou Jianying

2011-01-01

Objective: To establish the method of using the 12 th vertebrae for sex determination of adult Chinese and evaluate its effect. Methods: The 12 th thoracic vertebrae were developed by the clinic abdomen CT images. A total of 25 linear measurements on 7 aspects of the vertebrae were measured and 4 ratios were calculated. The items were selected which had the significant difference to establish the sex determination equation and its effect was evaluated. Results: Of the total 29 traits, 27 were sexually dimorphic (P<0.05), the accuracy was 56.3% - 89.2%, 8 traits had the accuracies mean or over 80.0%. The trait iVL had the highest accuracy of 89.2%. A function with four variables predicting sex with 90.8% accuracy was derived by using stepwise method of discriminant function analysis: Y=2.98 x iBDsm + 1.97 x PH + 3.37 x BHp + 3.27 x sVL/BHa - 32.80 (mean centroids= -7.69). Conclusion: The method of using the selected traits for sex determination of adult Chinese is practicable and it has a relatively high accuracy. (authors)

Sex determination of duck embryos: observations on syrinx development

Science.gov (United States)

Wilson, Robert E.; Sonsthagen, Sarah A.; Franson, J. Christian

2013-01-01

Ducks exhibit sexual dimorphism in vocal anatomy. Asymmetrical ossification of the syrinx (bulla syringealis) is discernable at about 10 days of age in male Pekin duck (Anas platyrhynchos domestica) embryos, but information is lacking on the early development of the bulla in wild ducks. To evaluate the reliability of this characteristic for sexing developing embryos, we examined the syrinx of dead embryos and compared results with molecular sexing techniques in high arctic nesting Common Eiders (Somateria mollissima). Embryos 8 days or older were accurately (100%) sexed based on the presence/absence of a bulla, 2 days earlier than Pekin duck. The use of the tracheal bulla can be a valuable technique when sex identification of embryos or young ducklings is required.

MPK-1 ERK Controls Membrane Organization in C. elegans Oogenesis via a Sex-Determination Module

OpenAIRE

Arur, Swathi; Ohmachi, Mitsue; Berkseth, Matt; Nayak, Sudhir; Hansen, David; Zarkower, David; Schedl, Tim

2011-01-01

Tissues that generate specialized cell-types in a production line must coordinate developmental mechanisms with physiological demand, although how this occurs is largely unknown. In the C. elegans hermaphrodite, the developmental sex-determination cascade specifies gamete sex in the distal germline, while physiological sperm signaling activates MPK-1/ERK in the proximal germline to control plasma membrane biogenesis/organization during oogenesis. We discovered repeated utilization of a self-c...

Interactive Effects of Culture and Sex Hormones on Sex Role Orientation

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Belinda ePletzer

2015-07-01

Full Text Available Sex role orientation, i.e. a person’s masculinity or femininity, influences cognitive and emotional performance, like biological sex. While it is now widely accepted that sex differences are modulated by the hormonal status of female participants (menstrual cycle, hormonal contraceptive use, the question, whether hormonal status and sex hormones also modulate participants sex role orientation has hardly been addressed previously. The present study assessed sex role orientation and hormonal status as well as sex hormone levels in three samples of participants from two different cultures (Northern American, Middle European. Menstrual cycle phase did not affect participant’s masculinity or femininity, but had a significant impact on reference group. While women in their follicular phase (low levels of female sex hormones determined their masculinity and femininity in reference to men, women in their luteal phase (high levels of female sex hormones determined their masculinity and femininity in reference to women. Hormonal contraceptive users rated themselves as significantly more feminine and less masculine than naturally cycling women. Furthermore, the impact of biological sex on the factorial structure of sex role orientation as well as the relationship of estrogen to masculinity/femininity was modulated by culture. We conclude that culture and sex hormones interactively affect sex role orientation and hormonal status of participants should be controlled for when assessing masculinity and/or femininity.

Clinical significance of serum sex hormones protein and lipid determination in patients with ulcerative colitis

International Nuclear Information System (INIS)

Song Qingzhang; Zhang Min

2010-01-01

Objective: To investigate the relationships between changes of serum sex hormones levels and protein-lipid metabolism in patients with ulcerative colitis. Methods: Serum levels of estradiol (E 2 ) pregnenedione (P), prolactin(PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH) (with CLIA), sree testos (T, with RIA) and total-protein (TP), albumin (Alb), globulin (G), albumin/globulinratio (A/G) total-cholesterd (TC), high density lipoprotein cholesterols (LDL-C) (with biochemistry were determined in 72 patients) with ulcerative colitis and 72 controls. Results: The serum levels of T, LH, FSH, TP, Alb, A/G, TC, LDL-C in patients with ulcerative colitis were significantly lower than those in controls (P 2 , PRL in patients with ulcerative colitis were significantly higher than those in controls (P 2 were negatively correlated with TP, A/G and TC (P 2 levels in the female sex (P>0.05) as well as between LH, FSH and T levels in the male sex (P>0.05). Conclusion: The abnormal serum levels of sex hormone might contribute to the development of hypoproteinaemia and lowered lipid levels in patients with ulcerative colitis. Treatment with correction of serum sex hormones levels might be beneficial to the patients. (authors)

Same Sex Marriage and the Perceived Assault on Opposite Sex Marriage

OpenAIRE

Dinno, Alexis; Whitney, Chelsea

2013-01-01

BACKGROUND: Marriage benefits both individuals and societies, and is a fundamental determinant of health. Until recently same sex couples have been excluded from legally recognized marriage in the United States. Recent debate around legalization of same sex marriage has highlighted for anti-same sex marriage advocates and policy makers a concern that allowing same sex couples to marry will lead to a decrease in opposite sex marriages. Our objective is to model state trends in opposite sex mar...

Phylogeny determines flower size-dependent sex allocation at flowering in a hermaphroditic family.

Science.gov (United States)

Teixido, A L; Guzmán, B; Staggemeier, V G; Valladares, F

2017-11-01

In animal-pollinated hermaphroditic plants, optimal floral allocation determines relative investment into sexes, which is ultimately dependent on flower size. Larger flowers disproportionally increase maleness whereas smaller and less rewarding flowers favour female function. Although floral traits are considered strongly conserved, phylogenetic relationships in the interspecific patterns of resource allocation to floral sex remain overlooked. We investigated these patterns in Cistaceae, a hermaphroditic family. We reconstructed phylogenetic relationships among Cistaceae species and quantified phylogenetic signal for flower size, dry mass and nutrient allocation to floral structures in 23 Mediterranean species using Blomberg's K-statistic. Lastly, phylogenetically-controlled correlational and regression analyses were applied to examine flower size-based allometry in resource allocation to floral structures. Sepals received the highest dry mass allocation, followed by petals, whereas sexual structures increased nutrient allocation. Flower size and resource allocation to floral structures, except for carpels, showed a strong phylogenetic signal. Larger-flowered species allometrically allocated more resources to maleness, by increasing allocation to corollas and stamens. Our results suggest a major role of phylogeny in determining interspecific changes in flower size and subsequent floral sex allocation. This implies that flower size balances the male-female function over the evolutionary history of Cistaceae. While allometric resource investment in maleness is inherited across species diversification, allocation to the female function seems a labile trait that varies among closely related species that have diversified into different ecological niches. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

The role of the transformer gene in sex determination and reproduction in the tephritid fruit fly, Bactrocera dorsalis (Hendel).

Science.gov (United States)

Peng, Wei; Zheng, Wenping; Handler, Alfred M; Zhang, Hongyu

2015-12-01

Transformer (tra) is a switch gene in the somatic sex-determination hierarchy that regulates sexual dimorphism based on RNA splicing in many insects. In tephritids, a Y-linked male determining gene (M) controls sex in the sex-determination pathway. Here, homologues of Drosophila tra and transformer-2 (tra-2) genes were isolated and characterized in Bactrocera dorsalis (Hendel), one of the most destructive agricultural insect pests in many Asian countries. Two male-specific and one female-specific isoforms of B. dorsalis transformer (Bdtra) were identified. The presence of multiple TRA/TRA-2 binding sites in Bdtra suggests that the TRA/TRA-2 proteins are splicing regulators promoting and maintaining, epigenetically, female sex determination by a tra positive feedback loop in XX individuals during development. The expression patterns of female-specific Bdtra transcripts during early embryogenesis shows that a peak appears at 15 h after egg laying. Using dsRNA to knock-down Bdtra expression in the embryo and adult stages, we showed that sexual formation is determined early in the embryo stage and that parental RNAi does not lead to the production of all male progeny as in Tribolium castaneum. RNAi results from adult abdominal dsRNA injections show that Bdtra has a positive influence on female yolk protein gene (Bdyp1) expression and fecundity.

Sex Determination Using Inion-Opistocranium-Asterion (IOA Triangle in Nigerians’ Skulls

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C. N. Orish

2014-01-01

Full Text Available Background. Determination of sex is an important concern to the forensic anthropologists as it is critical for individual identification. This study has investigated the existence of sexual dimorphism in the dimensions and the area of the IOA triangle. Methods. A total of 100 adult dry skulls, (78 males; 22 females from departments of anatomy in Nigerian universities were used for this study. Automatic digital calliper was used for the measurement. Coefficient of variation, correlation, linear regression, percentiles, and sexual dimorphism ratio were computed from the IOA triangle measurements. The IOA triangle area was compared between sexes. Results. The male parameters were significantly (P<0.05 higher than female parameters. The left opistocranium-asterion length was 71.09±0.56 and 61.68±3.35 mm and the right opistocranium-asterion length was 69.73±0.49 and 60.92±2.10 mm for male and female, respectively. A total area of IOA triangle of 1938.88 mm2 and 1305.68 mm2 for male and female, respectively, was calculated. The left IOA indices were 46.42% and 37.40% in males and females, respectively, while the right IOA indices for males and females were 47.19% and 38.87%, respectively. Conclusion. The anthropometry of inion-opistocranium-asterion IOA triangle can be a guide in gender determination of unknown individuals.

Gadd45g is essential for primary sex determination, male fertility and testis development.

Directory of Open Access Journals (Sweden)

Heiko Johnen

Full Text Available In humans and most mammals, differentiation of the embryonic gonad into ovaries or testes is controlled by the Y-linked gene SRY. Here we show a role for the Gadd45g protein in this primary sex differentiation. We characterized mice deficient in Gadd45a, Gadd45b and Gadd45g, as well as double-knockout mice for Gadd45ab, Gadd45ag and Gadd45bg, and found a specific role for Gadd45g in male fertility and testis development. Gadd45g-deficient XY mice on a mixed 129/C57BL/6 background showed varying degrees of disorders of sexual development (DSD, ranging from male infertility to an intersex phenotype or complete gonadal dysgenesis (CGD. On a pure C57BL/6 (B6 background, all Gadd45g(-/- XY mice were born as completely sex-reversed XY-females, whereas lack of Gadd45a and/or Gadd45b did not affect primary sex determination or testis development. Gadd45g expression was similar in female and male embryonic gonads, and peaked around the time of sex differentiation at 11.5 days post-coitum (dpc. The molecular cause of the sex reversal was the failure of Gadd45g(-/- XY gonads to achieve the SRY expression threshold necessary for testes differentiation, resulting in ovary and Müllerian duct development. These results identify Gadd45g as a candidate gene for male infertility and 46,XY sex reversal in humans.

Determinants of Human Papillomavirus Vaccination Intention Among Female Sex Workers in Amsterdam, the Netherlands

NARCIS (Netherlands)

Marra, E.; Dam, L. van; Kroone, N.; Alberts, C.J.; Craanen, M.; Zimet, G.D.; Heijmam, T.; Hogewoning, A.A.; Sonder, G.J.B.; Vries, H.J.C. de; Alberts, C.J.; Paulussen, T.G.W.M.; Schim van der Loeff, M.F.

2017-01-01

Introduction: Female sex workers (FSWs) are at risk for human papillomavirus (HPV)-induced diseases but are currently not targeted by the HPV vaccination program in the Netherlands. We explored determinants of their intention to get vaccinated against HPV in case vaccination would be offered to

determination of sex in south african blacks by discriminant function analysis of mandibular linear dimensions : A preliminary investigation using the zulu local population.

Science.gov (United States)

Franklin, Daniel; O'Higgins, Paul; Oxnard, Charles E; Dadour, Ian

2006-12-01

The determination of sex is a critical component in forensic anthropological investigation. The literature attests to numerous metrical standards, each utilizing diffetent skeletal elements, for sex determination in South A frican Blacks. Metrical standards are popular because they provide a high degree of expected accuracy and are less error-prone than subjective nonmetric visual techniques. We note, however, that there appears to be no established metric mandible discriminant function standards for sex determination in this population.We report here on a preliminary investigation designed to evaluate whether the mandible is a practical element for sex determination in South African Blacks. The sample analyzed comprises 40 nonpathological Zulu individuals drawn from the R.A. Dart Collection. Ten linear measurements, obtained from mathematically trans-formed three-dimensional landmark data, are analyzed using basic univariate statistics and discriminant function analyses. Seven of the 10 measurements examined are found to be sexually dimorphic; the dimensions of the ramus are most dimorphic. The sex classification accuracy of the discriminant functions ranged from 72.5 to 87.5% for the univariate method, 92.5% for the stepwise method, and 57.5 to 95% for the direct method. We conclude that the mandible is an extremely useful element for sex determination in this population.

Sex determination of baleen whale artefacts

DEFF Research Database (Denmark)

Sinding, Mikkel Holger Strander; Tervo, Outi M.; Grønnow, Bjarne

2016-01-01

to 4500 years old bowhead whale samples, and for comparison on dilution series from modern bowhead whales of known sex. DNA sequencing of PCR products obtained from the ancient material confirmed a higher proportion of successful PCR amplifications of the X homologue over the Y homologue. This potentially...

XX/XY system of sex determination in the geophilomorph centipede Strigamia maritima

Czech Academy of Sciences Publication Activity Database

Green, J. E.; Dalíková, Martina; Sahara, K.; Marec, František; Akam, M.

2016-01-01

Roč. 11, č. 2 (2016), č. článku e0150292. E-ISSN 1932-6203 R&D Projects: GA AV ČR IAA600960925; GA ČR(CZ) GA14-22765S Institutional support: RVO:60077344 Keywords : sex determination * Strigamia maritima * XX/XY system Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.806, year: 2016 http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0150292

Sox9 gene regulation and the loss of the XY/XX sex-determining mechanism in the mole vole Ellobius lutescens.

Science.gov (United States)

Bagheri-Fam, Stefan; Sreenivasan, Rajini; Bernard, Pascal; Knower, Kevin C; Sekido, Ryohei; Lovell-Badge, Robin; Just, Walter; Harley, Vincent R

2012-01-01

In most mammals, the Y chromosomal Sry gene initiates testis formation within the bipotential gonad, resulting in male development. SRY is a transcription factor and together with SF1 it directly up-regulates the expression of the pivotal sex-determining gene Sox9 via a 1.3-kb cis-regulatory element (TESCO) which contains an evolutionarily conserved region (ECR) of 180 bp. Remarkably, several rodent species appear to determine sex in the absence of Sry and a Y chromosome, including the mole voles Ellobius lutescens and Ellobius tancrei, whereas Ellobius fuscocapillus of the same genus retained Sry. The sex-determining mechanisms in the Sry-negative species remain elusive. We have cloned and sequenced 1.1 kb of E. lutescens TESCO which shares 75% sequence identity with mouse TESCO indicating that testicular Sox9 expression in E. lutescens might still be regulated via TESCO. We have also cloned and sequenced the ECRs of E. tancrei and E. fuscocapillus. While the three Ellobius ECRs are highly similar (94-97% sequence identity), they all display a 14-bp deletion (Δ14) removing a highly conserved SOX/TCF site. Introducing Δ14 into mouse TESCO increased both basal activity and SF1-mediated activation of TESCO in HEK293T cells. We propose a model whereby Δ14 may have triggered up-regulation of Sox9 in XX gonads leading to destabilization of the XY/XX sex-determining mechanism in Ellobius. E. lutescens/E. tancrei and E. fuscocapillus could have independently stabilized their sex determination mechanisms by Sry-independent and Sry-dependent approaches, respectively.

Fibromyalgia and Complementary Health Approaches

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... Musculoskeletal and Skin Diseases Web site . What the Science Says About Complementary Health Approaches for Fibromyalgia Mind ... Complementary and alternative medical therapies in fibromyalgia . Current Pharmaceutical Design . 2006;12(1):47–57. Sherman KJ, ...

Sex-Dependent Individual Differences and the Correlational Relationship Between Proprioceptive and Verbal Tests

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Liutsko Liudmila

2014-09-01

Full Text Available Introduction. The aim of the study was to analyze the relationship between proprioceptive and verbal tests on personality in both sexes separately due to existing proprioceptive differences in fine motor behavior between men and women in our previous studies [1, 2, 3]. Material and methods. 114 middle-aged participants from Belarus completed verbal tests (personality: Eysenck's EPQ, Big Five in Hromov's Russian adaptation, and Rosenberg's Self-esteem together with Proprioceptive Diagnostics of Temperament and Character (by Tous. Complementary information, such as tests of time perception, was collected and used in correlative and ANOVA analyses with the use of SPSS v.19. Results. The relationship between proprioceptive variables in personality and individual differences, time perception and the results of verbal tests were determined for each sex subgroup and discussed. ANOVA results reflected the corresponding differences and similarities between men and women in the variables of each test. Time perception was found to be significantly correlated to all five dimensions of the Big Five Test in both sexes, and both had a significant relationship to the same variables of the DP-TC test. Conclusions. Time perception can be used as an indirect indicator of personality. Existing individual and personality differences should be taken into account in coaching and education to obtain more effective results.

Multiple sex-associated regions and a putative sex chromosome in zebrafish revealed by RAD mapping and population genomics.

Directory of Open Access Journals (Sweden)

Jennifer L Anderson

Full Text Available Within vertebrates, major sex determining genes can differ among taxa and even within species. In zebrafish (Danio rerio, neither heteromorphic sex chromosomes nor single sex determination genes of large effect, like Sry in mammals, have yet been identified. Furthermore, environmental factors can influence zebrafish sex determination. Although progress has been made in understanding zebrafish gonad differentiation (e.g. the influence of germ cells on gonad fate, the primary genetic basis of zebrafish sex determination remains poorly understood. To identify genetic loci associated with sex, we analyzed F(2 offspring of reciprocal crosses between Oregon *AB and Nadia (NA wild-type zebrafish stocks. Genome-wide linkage analysis, using more than 5,000 sequence-based polymorphic restriction site associated (RAD-tag markers and population genomic analysis of more than 30,000 single nucleotide polymorphisms in our *ABxNA crosses revealed a sex-associated locus on the end of the long arm of chr-4 for both cross families, and an additional locus in the middle of chr-3 in one cross family. Additional sequencing showed that two SNPs in dmrt1 previously suggested to be functional candidates for sex determination in a cross of ABxIndia wild-type zebrafish, are not associated with sex in our AB fish. Our data show that sex determination in zebrafish is polygenic and that different genes may influence sex determination in different strains or that different genes become more important under different environmental conditions. The association of the end of chr-4 with sex is remarkable because, unique in the karyotype, this chromosome arm shares features with known sex chromosomes: it is highly heterochromatic, repetitive, late replicating, and has reduced recombination. Our results reveal that chr-4 has functional and structural properties expected of a sex chromosome.

Complementary medicine in chronic pain treatment.

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Simpson, Charles A

2015-05-01

This article discusses several issues related to therapies that are considered "complementary" or "alternative" to conventional medicine. A definition of "complementary and alternative medicine" (CAM) is considered in the context of the evolving health care field of complementary medicine. A rationale for pain physicians and clinicians to understand these treatments of chronic pain is presented. The challenges of an evidence-based approach to incorporating CAM therapies are explored. Finally, a brief survey of the evidence that supports several widely available and commonly used complementary therapies for chronic pain is provided. Copyright © 2015 Elsevier Inc. All rights reserved.

Sex determination from the frontal bone: a geometric morphometric study.

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Perlaza, Néstor A

2014-09-01

Sex estimation in human skeletal remains when using the cranium through traditional methods is a fundamental pillar in human identification; however, it may be possible to incur in a margin of error due because of the state of preservation in incomplete or fragmented remains. The aim of this investigation was sex estimation through the geometric morphometric analysis of the frontal bone. The sample employed 60 lateral radiographs of adult subjects of both sexes (30 males and 30 females), aged between 18 and 40 years, with mean age for males of 28 ± 4 and 30 ± 6 years for females. Thin-plate splines evidenced strong expansion of the glabellar region in males and contraction in females. No significant differences were found between sexes with respect to size. The findings suggest differences in shape and size in the glabellar region, besides reaffirming the use of geometric morphometrics as a quantitative method in sex estimation. © 2014 American Academy of Forensic Sciences.

Infant Feeding Practices and the Effect of Early Complementary ...

African Journals Online (AJOL)

Objective: The objective of this study was to determine infant feeding practices and the effect of early complementary feeding on the nutritional status of children in Makada Community, Sabon Gari Local Government Area (LGA), Kaduna State, Nigeria. Materials and Methods: A cross-sectional survey was carried out.

Self-Reported Use Of Traditional, Complementary And Over-The ...

African Journals Online (AJOL)

Current management of HIV involves the use of conventional prescription medicines, called 'antiretroviral drugs' (ARV), over-the-counter (OTC), complementary and alternative medicines (CAM), as well as African traditional medicine (ATM). The aim of this study was to determine the prevalence of use of traditional, ...

Sex determination and disorders of sex development according to the revised nomenclature and classification in 46,XX individuals.

Science.gov (United States)

Kousta, Eleni; Papathanasiou, Asteroula; Skordis, Nicos

2010-01-01

There have been considerable advances concerning understanding of the early and later stages of ovarian development; a number of genes have been implicated and their mutations have been associated with developmental abnormalities. The most important genes controlling the initial phase of gonadal development, identical in females and males, are Wilms' tumor suppressor 1 (WT1) and steroidogenic factor 1 (SF1). Four genes are likely to be involved in the subsequent stages of ovarian development (WNT4, DAX1, FOXL2 and RSPO1), but none is yet proven to be the ovarian determining factor. Changes in nomenclature and classification were recently proposed in order to incorporate genetic advances and substitute gender-based diagnostic labels in terminology. The term "disorders of sex development" (DSD) is proposed to substitute the previous term "intersex disorders". Three main categories have been used to describe DSD in the 46,XX individual: 1) disorders of gonadal (ovarian) development: ovotesticular DSD, previously named true hermaphroditism, testicular DSD, previously named XX males, and gonadal dysgenesis; 2) disorders related to androgen excess (congenital adrenal hyperplasia, aromatase deficiency and P450 oxidoreductase deficiency); and 3) other rare disorders. In this mini-review, recent advances concerning development of the genital system in 46,XX individuals and related abnormalities are discussed. Basic embryology of the ovary and molecular pathways determining ovarian development are reviewed, focusing on mutations disrupting normal ovarian development. Disorders of sex development according to the revised nomenclature and classification in 46,XX individuals are summarized, including genetic progress in the field.

[Sex and gender: Two different scientific domains to be clarified].

Science.gov (United States)

Fernández, Juan

2010-05-01

Nowadays, the word sex and its related terms (sexual differences, sexual roles and stereotypes), so common not long ago, seems to have been replaced by gender and its related terms (gender differences, gender roles and stereotypes). We can sometimes find both sex and gender sharing the same space in scientific articles, although referring to different domains. In this paper, I try to explain the need for a model that can integrate both of these complex domains of sex and gender, leading to two independent, although complementary, disciplines: Sexology and Genderology. In both cases, I start from a functional standpoint, which will give meaning to both disciplines' specificities, as it is meant to link contributions from different fields of knowledge. This approach can have consequences for research, education, the experience of women, men, and ambiguous individuals, and therapy.

[Patients with variations of sex development : an example of interdisciplinary care].

Science.gov (United States)

Phan-Hug, Franziska; Kraus, Cynthia; Paoloni-Giacobino, Ariane; Fellmann, Florence; Typaldou, Sophia-Anna; Ansermet, François; Alamo, Leonor; Eggert, Nadja; Pelet, Odile; Vial, Yvan; Muehlethaler, Vincent; Birraux, Jacques; Ramseyer, Pascal; Renteria, Saira-Christine; Dwyer, Andrew; Pitteloud, Nelly; Meyrat, Blaise J

2016-11-09

The medical, psychological and social aspects of disorders of sex development (DSD) represent a challenge for the management of these patients. However, advances in our understanding of the etiology and genetics of this condition, novel surgical approaches and the growing influence of patient groups as well as wider recognition of ethical issues have helped improve the care of patients with a DSD. Importantly, a multidisciplinary approach involving specialists is crucial for understanding and treating such rare and complex cases. According to the recommendations of the Swiss National Ethical Commission, we shall use the term « Variation of Sex Development » rather than « Disorder of Sex Development » in this publication. This article addresses the care of DSD patients throughout development from the point of view of specialists in complementary fields.

The evolution of sex chromosomes in organisms with separate haploid sexes.

Science.gov (United States)

Immler, Simone; Otto, Sarah Perin

2015-03-01

The evolution of dimorphic sex chromosomes is driven largely by the evolution of reduced recombination and the subsequent accumulation of deleterious mutations. Although these processes are increasingly well understood in diploid organisms, the evolution of dimorphic sex chromosomes in haploid organisms (U/V) has been virtually unstudied theoretically. We analyze a model to investigate the evolution of linkage between fitness loci and the sex-determining region in U/V species. In a second step, we test how prone nonrecombining regions are to degeneration due to accumulation of deleterious mutations. Our modeling predicts that the decay of recombination on the sex chromosomes and the addition of strata via fusions will be just as much a part of the evolution of haploid sex chromosomes as in diploid sex chromosome systems. Reduced recombination is broadly favored, as long as there is some fitness difference between haploid males and females. The degeneration of the sex-determining region due to the accumulation of deleterious mutations is expected to be slower in haploid organisms because of the absence of masking. Nevertheless, balancing selection often drives greater differentiation between the U/V sex chromosomes than in X/Y and Z/W systems. We summarize empirical evidence for haploid sex chromosome evolution and discuss our predictions in light of these findings. © 2015 The Author(s).

Accuracy and reliability in sex determination from skulls: a comparison of Fordisc® 3.0 and the discriminant function analysis.

Science.gov (United States)

Guyomarc'h, Pierre; Bruzek, Jaroslav

2011-05-20

Identification in forensic anthropology and the definition of a biological profile in bioarchaeology are essential to each of those fields and use the same methodologies. Sex, age, stature and ancestry can be conclusive or dispensable, depending on the field. The Fordisc(®) 3.0 computer program was developed to aid in the identification of the sex, stature and ancestry of skeletal remains by exploiting the Forensic Data Bank (FDB) and computing discriminant function analyses (DFAs). Although widely used, this tool has been recently criticised, principally when used to determine ancestry. Two sub-samples of individuals of known sex were drawn from French (n=50) and Thai (n=91) osteological collections and used to assess the reliability of sex determination using Fordisc(®) 3.0 with 12 cranial measurements. Comparisons were made using the whole FDB as well as using select groups, taking into account the posterior and typicality probabilities. The results of Fordisc(®) 3.0 vary between 52.2% and 77.8% depending on the options and groups selected. Tests of published discriminant functions and the computation of specific DFA were performed in order to discuss the applicability of this software and, overall, to question the pertinence of the use of DFA and linear distances in sex determination, in light of the huge cranial morphological variability. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Determine sex ratios of green turtles along the U.S. West Coast through examinations of hormones

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National Oceanic and Atmospheric Administration, Department of Commerce — A testosterone (T) enzyme-linked immunosorbent assay (ELISA) was validated for use with green turtle plasma in order to determine the sex of juvenile turtles. We...

Fibroblast growth factor receptor 2 regulates proliferation and Sertoli differentiation during male sex determination

Science.gov (United States)

Kim, Yuna; Bingham, Nathan; Sekido, Ryohei; Parker, Keith L.; Lovell-Badge, Robin; Capel, Blanche

2007-01-01

Targeted mutagenesis of Fgf9 in mice causes male-to-female sex reversal. Among the four FGF receptors, FGFR2 showed two highly specific patterns based on antibody staining, suggesting that it might be the receptor-mediating FGF9 signaling in the gonad. FGFR2 was detected at the plasma membrane in proliferating coelomic epithelial cells and in the nucleus in Sertoli progenitor cells. This expression pattern suggested that Fgfr2 might play more than one role in testis development. To test the hypothesis that Fgfr2 is required for male sex determination, we crossed mice carrying a floxed allele of Fgfr2 with two different Cre lines to induce a temporal or cell-specific deletion of this receptor. Results show that deletion of Fgfr2 in embryonic gonads phenocopies deletion of Fgf9 and leads to male-to-female sex reversal. Using these two Cre lines, we provide the first genetic evidence that Fgfr2 plays distinct roles in proliferation and Sertoli cell differentiation during testis development. PMID:17940049

Structure–function analysis of mouse Sry reveals dual essential roles of the C-terminal polyglutamine tract in sex determination

Science.gov (United States)

Zhao, Liang; Ng, Ee Ting; Davidson, Tara-Lynne; Longmuss, Enya; Urschitz, Johann; Elston, Marlee; Moisyadi, Stefan; Bowles, Josephine; Koopman, Peter

2014-01-01

The mammalian sex-determining factor SRY comprises a conserved high-mobility group (HMG) box DNA-binding domain and poorly conserved regions outside the HMG box. Mouse Sry is unusual in that it includes a C-terminal polyglutamine (polyQ) tract that is absent in nonrodent SRY proteins, and yet, paradoxically, is essential for male sex determination. To dissect the molecular functions of this domain, we generated a series of Sry mutants, and studied their biochemical properties in cell lines and transgenic mouse embryos. Sry protein lacking the polyQ domain was unstable, due to proteasomal degradation. Replacing this domain with irrelevant sequences stabilized the protein but failed to restore Sry’s ability to up-regulate its key target gene SRY-box 9 (Sox9) and its sex-determining function in vivo. These functions were restored only when a VP16 transactivation domain was substituted. We conclude that the polyQ domain has important roles in protein stabilization and transcriptional activation, both of which are essential for male sex determination in mice. Our data disprove the hypothesis that the conserved HMG box domain is the only functional domain of Sry, and highlight an evolutionary paradox whereby mouse Sry has evolved a novel bifunctional module to activate Sox9 directly, whereas SRY proteins in other taxa, including humans, seem to lack this ability, presumably making them dependent on partner proteins(s) to provide this function. PMID:25074915

Structure-function analysis of mouse Sry reveals dual essential roles of the C-terminal polyglutamine tract in sex determination.

Science.gov (United States)

Zhao, Liang; Ng, Ee Ting; Davidson, Tara-Lynne; Longmuss, Enya; Urschitz, Johann; Elston, Marlee; Moisyadi, Stefan; Bowles, Josephine; Koopman, Peter

2014-08-12

The mammalian sex-determining factor SRY comprises a conserved high-mobility group (HMG) box DNA-binding domain and poorly conserved regions outside the HMG box. Mouse Sry is unusual in that it includes a C-terminal polyglutamine (polyQ) tract that is absent in nonrodent SRY proteins, and yet, paradoxically, is essential for male sex determination. To dissect the molecular functions of this domain, we generated a series of Sry mutants, and studied their biochemical properties in cell lines and transgenic mouse embryos. Sry protein lacking the polyQ domain was unstable, due to proteasomal degradation. Replacing this domain with irrelevant sequences stabilized the protein but failed to restore Sry's ability to up-regulate its key target gene SRY-box 9 (Sox9) and its sex-determining function in vivo. These functions were restored only when a VP16 transactivation domain was substituted. We conclude that the polyQ domain has important roles in protein stabilization and transcriptional activation, both of which are essential for male sex determination in mice. Our data disprove the hypothesis that the conserved HMG box domain is the only functional domain of Sry, and highlight an evolutionary paradox whereby mouse Sry has evolved a novel bifunctional module to activate Sox9 directly, whereas SRY proteins in other taxa, including humans, seem to lack this ability, presumably making them dependent on partner proteins(s) to provide this function.

Distance and sex determine host plant choice by herbivorous beetles.

Directory of Open Access Journals (Sweden)

Daniel J Ballhorn

Full Text Available Plants respond to herbivore damage with the release of volatile organic compounds (VOCs. This indirect defense can cause ecological costs when herbivores themselves use VOCs as cues to localize suitable host plants. Can VOCs reliably indicate food plant quality to herbivores?We determined the choice behavior of herbivorous beetles (Chrysomelidae: Gynandrobrotica guerreroensis and Cerotoma ruficornis when facing lima bean plants (Fabaceae: Phaseolus lunatus with different cyanogenic potential, which is an important constitutive direct defense. Expression of inducible indirect defenses was experimentally manipulated by jasmonic acid treatment at different concentrations. The long-distance responses of male and female beetles to the resulting induced plant volatiles were investigated in olfactometer and free-flight experiments and compared to the short-distance decisions of the same beetles in feeding trials.Female beetles of both species were repelled by VOCs released from all induced plants independent of the level of induction. In contrast, male beetles were repelled by strongly induced plants, showed no significant differences in choice behavior towards moderately induced plants, but responded positively to VOCs released from little induced plants. Thus, beetle sex and plant VOCs had a significant effect on host searching behavior. By contrast, feeding behavior of both sexes was strongly determined by the cyanogenic potential of leaves, although females again responded more sensitively than males. Apparently, VOCs mainly provide information to these beetles that are not directly related to food quality. Being induced by herbivory and involved in indirect plant defense, such VOCs might indicate the presence of competitors and predators to herbivores. We conclude that plant quality as a food source and finding a potentially enemy-free space is more important for female than for male insect herbivores, whereas the presence of a slightly damaged

Evidence for the evolutionary nascence of a novel sex determination pathway in honeybees

DEFF Research Database (Denmark)

Hasselmann, Martin; Gempe, Tanja; Schiøtt, Morten

2008-01-01

and hemizygotes (haploid individuals) are males. Although at least 15 different csd alleles are known among natural bee populations, the mechanisms linking allelic interactions to switching of the sexual development programme are still obscure. Here we report a new component of the sex-determining pathway...... in honeybees, encoded 12 kilobases upstream of csd. The gene feminizer (fem) is the ancestrally conserved progenitor gene from which csd arose and encodes an SR-type protein, harbouring an Arg/Ser-rich domain. Fem shares the same arrangement of Arg/Ser- and proline-rich-domain with the Drosophila principal sex......, whereas the female-specific splice variant encodes the functional protein. We show that RNA interference (RNAi)-induced knockdowns of the female-specific fem splice variant result in male bees, indicating that the fem product is required for entire female development. Furthermore, RNAi-induced knockdowns...

Complementary arsenic speciation methods: A review

Energy Technology Data Exchange (ETDEWEB)

Nearing, Michelle M., E-mail: michelle.nearing@rmc.ca; Koch, Iris, E-mail: koch-i@rmc.ca; Reimer, Kenneth J., E-mail: reimer-k@rmc.ca

2014-09-01

The toxicity of arsenic greatly depends on its chemical form and oxidation state (speciation) and therefore accurate determination of arsenic speciation is a crucial step in understanding its chemistry and potential risk. High performance liquid chromatography with inductively coupled mass spectrometry (HPLC–ICP-MS) is the most common analysis used for arsenic speciation but it has two major limitations: it relies on an extraction step (usually from a solid sample) that can be incomplete or alter the arsenic compounds; and it provides no structural information, relying on matching sample peaks to standard peaks. The use of additional analytical methods in a complementary manner introduces the ability to address these disadvantages. The use of X-ray absorption spectroscopy (XAS) with HPLC–ICP-MS can be used to identify compounds not extracted for HPLC–ICP-MS and provide minimal processing steps for solid state analysis that may help preserve labile compounds such as those containing arsenic-sulfur bonds, which can degrade under chromatographic conditions. On the other hand, HPLC–ICP-MS is essential in confirming organoarsenic compounds with similar white line energies seen by using XAS, and identifying trace arsenic compounds that are too low to be detected by XAS. The complementary use of electrospray mass spectrometry (ESI–MS) with HPLC–ICP-MS provides confirmation of arsenic compounds identified during the HPLC–ICP-MS analysis, identification of unknown compounds observed during the HPLC–ICP-MS analysis and further resolves HPLC–ICP-MS by identifying co-eluting compounds. In the complementary use of HPLC–ICP-MS and ESI–MS, HPLC–ICP-MS helps to focus the ESI–MS selection of ions. Numerous studies have shown that the information obtained from HPLC–ICP-MS analysis can be greatly enhanced by complementary approaches. - Highlights: • HPLC–ICP-MS is the most common method used for arsenic speciation. • HPLC limitations include

Complementary arsenic speciation methods: A review

International Nuclear Information System (INIS)

Nearing, Michelle M.; Koch, Iris; Reimer, Kenneth J.

2014-01-01

The toxicity of arsenic greatly depends on its chemical form and oxidation state (speciation) and therefore accurate determination of arsenic speciation is a crucial step in understanding its chemistry and potential risk. High performance liquid chromatography with inductively coupled mass spectrometry (HPLC–ICP-MS) is the most common analysis used for arsenic speciation but it has two major limitations: it relies on an extraction step (usually from a solid sample) that can be incomplete or alter the arsenic compounds; and it provides no structural information, relying on matching sample peaks to standard peaks. The use of additional analytical methods in a complementary manner introduces the ability to address these disadvantages. The use of X-ray absorption spectroscopy (XAS) with HPLC–ICP-MS can be used to identify compounds not extracted for HPLC–ICP-MS and provide minimal processing steps for solid state analysis that may help preserve labile compounds such as those containing arsenic-sulfur bonds, which can degrade under chromatographic conditions. On the other hand, HPLC–ICP-MS is essential in confirming organoarsenic compounds with similar white line energies seen by using XAS, and identifying trace arsenic compounds that are too low to be detected by XAS. The complementary use of electrospray mass spectrometry (ESI–MS) with HPLC–ICP-MS provides confirmation of arsenic compounds identified during the HPLC–ICP-MS analysis, identification of unknown compounds observed during the HPLC–ICP-MS analysis and further resolves HPLC–ICP-MS by identifying co-eluting compounds. In the complementary use of HPLC–ICP-MS and ESI–MS, HPLC–ICP-MS helps to focus the ESI–MS selection of ions. Numerous studies have shown that the information obtained from HPLC–ICP-MS analysis can be greatly enhanced by complementary approaches. - Highlights: • HPLC–ICP-MS is the most common method used for arsenic speciation. • HPLC limitations include

A microsatellite-based linkage map of salt tolerant tilapia (Oreochromis mossambicus x Oreochromis spp.) and mapping of sex-determining loci

Science.gov (United States)

2013-01-01

Background Tilapia is the common name for a group of cichlid fishes and is one of the most important aquacultured freshwater food fish. Mozambique tilapia and its hybrids, including red tilapia are main representatives of salt tolerant tilapias. A linkage map is an essential framework for mapping QTL for important traits, positional cloning of genes and understanding of genome evolution. Results We constructed a consensus linkage map of Mozambique tilapia and red tilapia using 95 individuals from two F1 families and 401 microsatellites including 282 EST-derived markers. In addition, we conducted comparative mapping and searched for sex-determining loci on the whole genome. These 401 microsatellites were assigned to 22 linkage groups. The map spanned 1067.6 cM with an average inter-marker distance of 3.3 cM. Comparative mapping between tilapia and stickleback, medaka, pufferfish and zebrafish revealed clear homologous relationships between chromosomes from different species. We found evidence for the fusion of two sets of two independent chromosomes forming two new chromosome pairs, leading to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex determination locus in Mozambique tilapia was mapped on LG1, and verified in five families containing 549 individuals. The major XY sex determination locus in red tilapia was located on LG22, and verified in two families containing 275 individuals. Conclusions A first-generation linkage map of salt tolerant tilapia was constructed using 401 microsatellites. Two separate fusions of two sets of two independent chromosomes may lead to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex-determining loci from Mozambique tilapia and red tilapia were mapped on LG1 and LG22, respectively. This map provides a useful resource for QTL mapping for important traits and comparative genome studies. The DNA markers linked to the sex-determining loci could be used in

A microsatellite-based linkage map of salt tolerant tilapia (Oreochromis mossambicus x Oreochromis spp. and mapping of sex-determining loci

Directory of Open Access Journals (Sweden)

Liu Feng

2013-01-01

Full Text Available Abstract Background Tilapia is the common name for a group of cichlid fishes and is one of the most important aquacultured freshwater food fish. Mozambique tilapia and its hybrids, including red tilapia are main representatives of salt tolerant tilapias. A linkage map is an essential framework for mapping QTL for important traits, positional cloning of genes and understanding of genome evolution. Results We constructed a consensus linkage map of Mozambique tilapia and red tilapia using 95 individuals from two F1 families and 401 microsatellites including 282 EST-derived markers. In addition, we conducted comparative mapping and searched for sex-determining loci on the whole genome. These 401 microsatellites were assigned to 22 linkage groups. The map spanned 1067.6 cM with an average inter-marker distance of 3.3 cM. Comparative mapping between tilapia and stickleback, medaka, pufferfish and zebrafish revealed clear homologous relationships between chromosomes from different species. We found evidence for the fusion of two sets of two independent chromosomes forming two new chromosome pairs, leading to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex determination locus in Mozambique tilapia was mapped on LG1, and verified in five families containing 549 individuals. The major XY sex determination locus in red tilapia was located on LG22, and verified in two families containing 275 individuals. Conclusions A first-generation linkage map of salt tolerant tilapia was constructed using 401 microsatellites. Two separate fusions of two sets of two independent chromosomes may lead to a reduction of 24 chromosome pairs in their ancestor to 22 pairs in tilapias. The XY sex-determining loci from Mozambique tilapia and red tilapia were mapped on LG1 and LG22, respectively. This map provides a useful resource for QTL mapping for important traits and comparative genome studies. The DNA markers linked to the sex-determining

Sexual dimorphism in mammalian autosomal gene regulation is determined not only by Sry but by sex chromosome complement as well.

Science.gov (United States)

Wijchers, Patrick J; Yandim, Cihangir; Panousopoulou, Eleni; Ahmad, Mushfika; Harker, Nicky; Saveliev, Alexander; Burgoyne, Paul S; Festenstein, Richard

2010-09-14

Differences between males and females are normally attributed to developmental and hormonal differences between the sexes. Here, we demonstrate differences between males and females in gene silencing using a heterochromatin-sensitive reporter gene. Using "sex-reversal" mouse models with varying sex chromosome complements, we found that this differential gene silencing was determined by X chromosome complement, rather than sex. Genome-wide transcription profiling showed that the expression of hundreds of autosomal genes was also sensitive to sex chromosome complement. These genome-wide analyses also uncovered a role for Sry in modulating autosomal gene expression in a sex chromosome complement-specific manner. The identification of this additional layer in the establishment of sexual dimorphisms has implications for understanding sexual dimorphisms in physiology and disease. Copyright © 2010 Elsevier Inc. All rights reserved.

Female heterogamety in Madagascar chameleons (Squamata: Chamaeleonidae: Furcifer): differentiation of sex and neo-sex chromosomes

Science.gov (United States)

Rovatsos, Michail; Pokorná, Martina Johnson; Altmanová, Marie; Kratochvíl, Lukáš

2015-01-01

Amniotes possess variability in sex determining mechanisms, however, this diversity is still only partially known throughout the clade and sex determining systems still remain unknown even in such a popular and distinctive lineage as chameleons (Squamata: Acrodonta: Chamaeleonidae). Here, we present evidence for female heterogamety in this group. The Malagasy giant chameleon (Furcifer oustaleti) (chromosome number 2n = 22) possesses heteromorphic Z and W sex chromosomes with heterochromatic W. The panther chameleon (Furcifer pardalis) (2n = 22 in males, 21 in females), the second most popular chameleon species in the world pet trade, exhibits a rather rare Z1Z1Z2Z2/Z1Z2W system of multiple sex chromosomes, which most likely evolved from W-autosome fusion. Notably, its neo-W chromosome is partially heterochromatic and its female-specific genetic content has expanded into the previously autosomal region. Showing clear evidence for genotypic sex determination in the panther chameleon, we resolve the long-standing question of whether or not environmental sex determination exists in this species. Together with recent findings in other reptile lineages, our work demonstrates that female heterogamety is widespread among amniotes, adding another important piece to the mosaic of knowledge on sex determination in amniotes needed to understand the evolution of this important trait. PMID:26286647

Nutritional and functional properties of a complementary food based ...

African Journals Online (AJOL)

The objective of this study was to determine the nutritional and functional properties of Amaranthus cruentus grain grown in Kenya for preparation of a ready-to-eat product that can be recommended as infant complementary food. Amaranth grains were subjected to steeping and steam pre-gelatinization to produce a ...

Interest in and Willingness to Use Complementary, Alternative and ...

African Journals Online (AJOL)

Background: Healthcare systems worldwide are changing and the use of complementary, alternative and traditional medicine (CAM) form part of this transformation. South Africa has a large number of CAM practitioners, but they are not included in the official healthcare system. The aim of this study was to determine the ...

Polytene chromosomes of monogenic and amphogenic Chrysomya species (Calliphoridae, Diptera): analysis of banding patterns and in situ hybridization with Drosophila sex determining gene sequences.

Science.gov (United States)

Puchalla, S

1994-03-01

Standard maps for the five banded polytene chromosomes found in trichogen cell nuclei of the monogenic blowfly Chrysomya rufifacies and the amphogenic Chrysomya pinguis are presented. The chromosomes are highly homologous in the two species; differences in banding patterns are predominantly caused by one pericentric and ten paracentric inversions. In chromosome 5 of the amphogenic Chrysomya phaonis, also analysed in this paper, an additional paracentric inversion was observed. The distribution of species specific inversions indicates that the monogenic C. rufifacies is phylogenetically older than the amphogenic species. The maternal sex realizer locus F'/f on polytene chromosome 5 of C. rufifacies is not associated with a structural heterozygosity. Chromosome pair 6 of C. rufifacies and the sex chromosome pair of C. pinguis are under-replicated in polytene nuclei; they consist of irregular chromatin granules, frequently associated with nucleolus material. Evolution of heteromorphic sex chromosomes in Chrysomya is probably correlated with heterochromatin accumulation. A search for sex determining genes in Chrysomya was initiated using sex determining sequences from Drosophila melanogaster for in situ hybridization. The polytene band 41A1 on chromosome 5 of monogenic and amphogenic Chrysomya species contains sequences homologous to the maternal sex determining gene daughterless (da). Homology to the zygotic gene Sex-lethal (Sxl) of Drosophila is detected in band 39A1 on chromosome 5 of C. rufifacies. The findings reported here are the first evidence for a possible homology between the da gene of Drosophila and the maternal sex realizer F' of C. rufifacies. An hypothesis for the evolution of the maternal effect sex determination of C. rufifacies is proposed.

An invasive social insect overcomes genetic load at the sex locus.

Science.gov (United States)

Gloag, Rosalyn; Ding, Guiling; Christie, Joshua R; Buchmann, Gabriele; Beekman, Madeleine; Oldroyd, Benjamin P

2016-11-07

Some invasive hymenopteran social insects found new populations with very few reproductive individuals. This is despite the high cost of founder effects for such insects, which generally require heterozygosity at a single locus-the complementary sex determiner, csd-to develop as females. Individuals that are homozygous at csd develop as either infertile or subfertile diploid males or not at all. Furthermore, diploid males replace the female workers that are essential for colony function. Here we document how the Asian honey bee (Apis cerana) overcame the diploid male problem during its invasion of Australia. Natural selection prevented the loss of rare csd alleles due to genetic drift and corrected the skew in allele frequencies caused by founder effects to restore high average heterozygosity. Thus, balancing selection can alleviate the genetic load at csd imposed by severe bottlenecks, and so facilitate invasiveness.

The fate of W chromosomes in hybrids between wild silkmoths, Samia cynthia ssp.: no role in sex determination and reproduction.

Science.gov (United States)

Yoshido, A; Marec, F; Sahara, K

2016-05-01

Moths and butterflies (Lepidoptera) have sex chromosome systems with female heterogamety (WZ/ZZ or derived variants). The maternally inherited W chromosome is known to determine female sex in the silkworm, Bombyx mori. However, little is known about the role of W chromosome in other lepidopteran species. Here we describe two forms of the W chromosome, W and neo-W, that are transmitted to both sexes in offspring of hybrids from reciprocal crosses between subspecies of wild silkmoths, Samia cynthia. We performed crosses between S. c. pryeri (2n=28, WZ/ZZ) and S. c. walkeri (2n=26, neo-Wneo-Z/neo-Zneo-Z) and examined fitness and sex chromosome constitution in their hybrids. The F1 hybrids of both reciprocal crosses had reduced fertility. Fluorescence in situ hybridization revealed not only the expected sex chromosome constitutions in the backcross and F2 hybrids of both sexes but also females without the W (or neo-W) chromosome and males carrying the W (or neo-W) chromosome. Furthermore, crosses between the F2 hybrids revealed no association between the presence or absence of W (or neo-W) chromosome and variations in the hatchability of their eggs. Our results clearly suggest that the W (or neo-W) chromosome of S. cynthia ssp. plays no role in sex determination and reproduction, and thus does not contribute to the formation of reproductive barriers between different subspecies.

Sex determination in beetles: Production of all male progeny by Parental RNAi knockdown of transformer

Science.gov (United States)

Shukla, Jayendra Nath; Palli, Subba Reddy

2012-01-01

Sex in insects is determined by a cascade of regulators ultimately controlling sex-specific splicing of a transcription factor, Doublesex (Dsx). We recently identified homolog of dsx in the red flour beetle, Tribolium castaneum (Tcdsx). Here, we report on the identification and characterization of a regulator of Tcdsx splicing in T. castaneum. Two male-specific and one female-specific isoforms of T. castaneum transformer (Tctra) were identified. RNA interference-aided knockdown of Tctra in pupa or adults caused a change in sex from females to males by diverting the splicing of Tcdsx pre-mRNA to male-specific isoform. All the pupa and adults developed from Tctra dsRNA injected final instar larvae showed male-specific sexually dimorphic structures. Tctra parental RNAi caused an elimination of females from the progeny resulting in production of all male progeny. Transformer parental RNAi could be used to produce all male population for use in pest control though sterile male release methods. PMID:22924109

On the origin of sex chromosomes from meiotic drive

Science.gov (United States)

Úbeda, Francisco; Patten, Manus M.; Wild, Geoff

2015-01-01

Most animals and many plants make use of specialized chromosomes (sex chromosomes) to determine an individual's sex. Best known are the XY and ZW sex-determination systems. Despite having evolved numerous times, sex chromosomes present something of an evolutionary puzzle. At their origin, alleles that dictate development as one sex or the other (primitive sex chromosomes) face a selective penalty, as they will be found more often in the more abundant sex. How is it possible that primitive sex chromosomes overcome this disadvantage? Any theory for the origin of sex chromosomes must identify the benefit that outweighs this cost and enables a sex-determining mutation to establish in the population. Here we show that a new sex-determining allele succeeds when linked to a sex-specific meiotic driver. The new sex-determining allele benefits from confining the driving allele to the sex in which it gains the benefit of drive. Our model requires few special assumptions and is sufficiently general to apply to the evolution of sex chromosomes in outbreeding cosexual or dioecious species. We highlight predictions of the model that can discriminate between this and previous theories of sex-chromosome origins. PMID:25392470

Complementary Cohort Strategy for Multimodal Face Pair Matching

DEFF Research Database (Denmark)

Sun, Yunlian; Nasrollahi, Kamal; Sun, Zhenan

2016-01-01

Face pair matching is the task of determining whether two face images represent the same person. Due to the limited expressive information embedded in the two face images as well as various sources of facial variations, it becomes a quite difficult problem. Towards the issue of few available images...... provided to represent each face, we propose to exploit an extra cohort set (identities in the cohort set are different from those being compared) by a series of cohort list comparisons. Useful cohort coefficients are then extracted from both sorted cohort identities and sorted cohort images...... for complementary information. To augment its robustness to complicated facial variations, we further employ multiple face modalities owing to their complementary value to each other for the face pair matching task. The final decision is made by fusing the extracted cohort coefficients with the direct matching...

Effect of exogenous estradiol applied at different embryonic stages on sex determination, growth, and mortality in the leopard gecko (Eublepharis macularius).

Science.gov (United States)

Tousignant, A; Crews, D

1994-01-01

Temperature-dependent sex determination (TSD) occurs in three orders of reptiles. Several studies have examined the ability of estradiol to produce female hatchlings incubated at a male-producing temperature. The results of these experiments support the idea that estradiol could be used as a powerful tool in the conservation of endangered species with TSD by manipulating hatchling sex ratios. However, these experiments have concentrated on the mechanism of determination. This experiment was designed to test the efficacy of various dosages of estradiol applied at two different stages to alter the hatchling sex ratio as well as determining the potential use of such manipulation for conservation efforts by monitoring egg mortality and hatchling growth. The leopard gecko (Eublepharis macularius) exhibits TSD and reaches reproductive maturity in less than one year, making it an excellent model for evaluating the long-term effects of estradiol. The results demonstrate that estradiol has a dose-dependent effect on the hatchling sex ratio while only high dosages applied at the later stage of development showed increased mortality. Estrogen-determined females grew at the same rate as temperature-determined females and have produced viable hatchlings. Estradiol treatment of eggs from endangered species may provide a method of insuring female offspring when the TSD pattern is unknown or equipment for controlled incubation is unavailable.

Thyroid Disease and Complementary and Alternative Medicine (CAM)

Science.gov (United States)

... Alternative Medicine in Thyroid Disease Complementary and Alternative Medicine in Thyroid Disease (CAM) WHAT IS COMPLEMENTARY AND ALTERNATIVE MEDICINE (CAM)? Complementary and Alternative Medicine (CAM) is defined ...

Sex determination in Turdus amaurochalinus (Passeriformes: Muscicapidae: morphometrical analysis supported by CHD gene

Directory of Open Access Journals (Sweden)

Katyucha Von Kossel de Andrade Silva

2011-06-01

Full Text Available Sex determination is important for conservation and population studies, particularly for reproduction programs of threatened species and behavioural ecology. Turdus amaurochalinus, Creamy-bellied Thrush, only exhibits sexual dimorphism during the breeding season, when males are considered to show intense yellow bills, and females and immature males show dark brown bills. The objectives of this study were: 1 to determine the sex of individuals using genetic techniques, and 2 to test the hypothesis that sex dimorphism can be detected by morphometry. This study was carried out at Parque Nacional da Restinga de Jurubatiba, a preserved area located on the North coast of Rio de Janeiro State. The birds were captured using ornithological nets, singly marked with metal rings, weighed, measured and had blood samples collected before being released. The sex of 42 T. amaurochalinus individuals was determined using the CHD gene marker. A total of 20 males and 22 females were identified from June to August, with peak capture frequency in June. Turdus amaurochalinus females and males differed significantly in morphometrical measures. The most important traits to distinguish males from females were wing length (Student t-test=4.34, df=40, p=0.0001 and weight (Student t-test=2.08,df=40, p=0.044: females were heavier and had significantly shorter wing length than males. Females and males were correctly classified in 86% and 75% of cases, respectively, using Discriminant Analysis. The molecular analysis was the most secure method for sex determination in the studied species. Rev. Biol. Trop. 59 (2: 789- 794. Epub 2011 June 01.La determinación del sexo es importante para la conservación y los estudios poblacionales. Turdus amaurochalinus no presenta aparente dimorfismo sexual. El objetivo de este estudio fue determinar el sexo a través de una técnica genética, mediante el uso del marcador del gen CHD y se puso a prueba la hipótesis de que el dimorfismo

Use of complementary and alternative medicine by patients with cancer in northern Turkey: analysis of cost and satisfaction.

Science.gov (United States)

Aydin Avci, Ilknur; Koç, Zeliha; Sağlam, Zeynep

2012-03-01

The aims of this study were to determine (1) the prevalence of complementary and alternative medicine use among patients with cancer, (2) the method of use of the particular therapy, (3) the reasons for using complementary and alternative medicine therapies, (4) the benefits experienced by the use of complementary and alternative medicine, (5) the source of information about complementary and alternative medicine therapies and, (6) the satisfaction and cost of complementary and alternative medicine. Complementary and alternative medicine consists of diverse medical and healthcare systems, practices and products that are not considered at present to be a part of conventional medicine. The majority of patients who use complementary and alternative medicine use more than one method. Complementary and alternative medicine use is more common in cases of advanced disease or poor prognosis. This is a descriptive study of complementary and alternative medicine. This study was conducted in the Chemotherapy Unit at Ondokuz Mayıs University, Faculty of Medicine, Samsun, Turkey, between 18 March 2008-30 June 2008. Two hundred fifty-three patients with cancer, among 281 patients who applied to the chemotherapy clinic between these dates, agreed to take part in the study with whom contact could be made were included. A questionnaire including descriptive characteristics in collecting data, characteristics about diseases and their treatments, complementary and alternative medicine information and implementation situations and a control list about complementary and alternative medicine implementations were given. The collected data were evaluated by computer using descriptive statistics, the chi-square test and Student's t-test. In this study, 94·1% of the patients were content with medical treatment, 58·9% of them used complementary and alternative medicine treatments, 41·1% did not use any complementary and alternative medicine treatments. The satisfaction level of the

Timing of introduction of complementary food: short- and long-term health consequences.

Science.gov (United States)

Przyrembel, Hildegard

2012-01-01

Complementary food is needed when breast milk (or infant formula) alone is no longer sufficient for both nutritional and developmental reasons. The timing of its introduction, therefore, is an individual decision, although 6 months of exclusive breastfeeding can be recommended for most healthy term infants. The new foods are intended to 'complement' ongoing breastfeeding with those dietary items whose intake has become marginal or insufficient. Both breastfeeding and complementary feeding can have direct or later consequences on health. The evaluation of consequences of both early and late introduction of complementary food can neither disregard the effect of breastfeeding compared to formula feeding nor the composition or quality of the complementary food. Possible short-term health effects concern growth velocity and infections, and possible long-term effects may relate to atopic diseases, type 1 and 2 diabetes, obesity and neuromuscular development. On the basis of the currently available evidence, it is impossible to exactly determine the age when risks related to the start of complementary feeding are lowest or highest for most of these effects, with the possible exception of infections and early growth velocity. The present knowledge on undesirable health effects, however, is mainly based on observational studies, and although some mechanisms have been proposed, further prospective studies have to clarify these unsolved issues. Even less evidence on the consequences of the timing of complementary food introduction is available for formula-fed infants. Copyright © 2012 S. Karger AG, Basel.

An Overview of Age, Sex and Race Determination from Teeth and Skull

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Manas Gupta

2015-01-01

Full Text Available Background : Forensic dentistry represents the overlap between the dental and legal professions. Throughout this century, odontological examinations have been a critical determinant in the search for identity of individual remains. Dental maturity has played an important role in estimating the chronological age of individuals. Age estimation is a sub-discipline of the forensic sciences and should be an important part of every identification process, especially when information relating to the deceased is unavailable. Forensic dentist helps in identification of deceased victims by age, sex and race determination from teeth and skull. Since the scope of forensic odontology is very broad and challenging, dental surgeons trained in forensic odontology can make unique contributions in the administration of justice, which is the key note of democracy.

Radioimmunological methods of determining hormones in the blood in physiological pregnancy and in abortions and premature delivery

International Nuclear Information System (INIS)

Bulienko, S.D.; Fogel, P.I.

1981-01-01

Significant changes are shown to occur in the level of sex hormones in blood at the risk of spontaneous abortion, missed abortion, or the mole. Determining the levels of estradiol, progesterone, chorial gonadotropin and testosterone in the blood serum using RIA yields immediate information on the hormonal function of the fetoplacental unit. This has diagnostic significance and can be used as a criterion for the application of complementary hormonal therapy when there is a risk of abortion or premature delivery. (author)

Temperature-dependent sex determination in the leopard gecko, Eublepharis macularius.

Science.gov (United States)

Viets, B E; Tousignant, A; Ewert, M A; Nelson, C E; Crews, D

1993-05-01

The leopard gecko, Eublepharis macularius, has temperature-dependent sex determination (TSD). Previous reports have shown that females are produced predominantly at cool incubation temperatures and males are produced predominantly at warm incubation temperatures (Pattern Ib). We report here that incubation at even higher temperatures (34 and 35 degrees C) produces mostly females (Pattern II). The lethal maximum constant incubation temperature for this species appears to be just above 35 degrees C. Although a previous study indicated that females from a warm incubation temperature (32 degrees C) failed to lay eggs, we found that 12 of 14 mature females incubated at 32.5 degrees C, and 5 of 6 mature females incubated at 34 degrees C produced fertile eggs and viable hatchlings.

Label-free detection of sex determining region Y (SRY) via capacitive biosensor

KAUST Repository

Sivashankar, Shilpa

2016-10-20

In this work, we present for the first time, the use of a simple fractal capacitive biosensor for the quantification and detection of sex-determining region Y (SRY) genes. This section of genetic code, which is found on the Y chromosome, finds importance for study as it causes fetuses to develop characteristics of male sex-like gonads when a mutation occurs. It is also an important genetic code in men, and disorders involving the SRY gene can cause infertility and sexual malfunction that lead to a variety of gene mutational disorders. We have therefore designed silicon-based, label-free fractal capacitive biosensors to quantify various proteins and genes. We take advantage of a good dielectric material, Parylene C for enhancing the performance of the sensors. We have integrated these sensors with a simple microchannel for easy handling of fluids on the detection area. The read-out value of an Agilent LCR meter used to measure capacitance of the sensor at a frequency of 1 MHz determined gene specificity and gene quantification. These data revealed that the capacitance measurement of the capacitive biosensor for the SRY gene depended on both the target and the concentration of DNA. The experimental outcomes in the present study can be used to detect DNA and its variations in crucial fields that have a great impact on our daily lives, such as clinical and veterinary diagnostics, industrial and environmental testing and forensic sciences.

[Complementary and alternative medicine in oncology].

Science.gov (United States)

Hübner, J

2013-06-01

Complementary and alternative medicine are frequently used by cancer patients. The main benefit of complementary medicine is that it gives patients the chance to become active. Complementary therapy can reduce the side effects of conventional therapy. However, we have to give due consideration to side effects and interactions: the latter being able to reduce the effectiveness of cancer therapy and so to jeopardise the success of therapy. Therefore, complementary therapy should be managed by the oncologist. It is based on a common concept of cancerogenesis with conventional therapy. Complement therapy can be assessed in studies. Alternative medicine in contrast rejects common rules of evidence-based medicine. It starts from its own concepts of cancerogenesis, which is often in line with the thinking of lay persons. Alternative medicine is offered as either "alternative" to recommended cancer treatment or is used at the same time but without due regard for the interactions. Alternative medicine is a high risk to patients. In the following two parts of the article, the most important complementary and alternative therapies cancer patients use nowadays are presented and assessed according to published evidence.

A complex interaction of imprinted and maternal-effect genes modifies sex determination in Odd Sex (Ods) mice.

Science.gov (United States)

Poirier, Christophe; Qin, Yangjun; Adams, Carolyn P; Anaya, Yanett; Singer, Jonathan B; Hill, Annie E; Lander, Eric S; Nadeau, Joseph H; Bishop, Colin E

2004-11-01

The transgenic insertional mouse mutation Odd Sex (Ods) represents a model for the long-range regulation of Sox9. The mutation causes complete female-to-male sex reversal by inducing a male-specific expression pattern of Sox9 in XX Ods/+ embryonic gonads. We previously described an A/J strain-specific suppressor of Ods termed Odsm1(A). Here we show that phenotypic sex depends on a complex interaction between the suppressor and the transgene. Suppression can be achieved only if the transgene is transmitted paternally. In addition, the suppressor itself exhibits a maternal effect, suggesting that it may act on chromatin in the early embryo.

[Complementary and alternative medicine: use in Montes Claros, Minas Gerais].

Science.gov (United States)

Neto, Joao Felício Rodrigues; Faria, Anderson Antônio de; Figueiredo, Maria Fernanda Santos

2009-01-01

To determine prevalence of utilization and social and economic profile of those using complementary and alternative medicine in the medium sized Brazilian city of Montes Claros, MG. A transversal descriptive study was conducted. The sample of 3090 people was probabilistic, by clusters using the household as the sample unit for interview of both genders, older than 18 years. Data were collected by semi-structured questionnaires. Utilization of complementary and alternative medicine was of 8.9% when only those involving costs such as homeopathy, acupuncture, chiropractics, techniques of relaxation/ meditation and massage are considered and of 70.0%, when all therapies found were included. Prevalent were prayers to God (52.0%), popular medicines (30.9%), physical exercises (25.5%), faith healers (15.0%), popular diets (7.1%), massage (4.9%), relaxation/meditation (2.8%), homeopathy (2.4%), and groups of self-help (1.9%), chiropractics (1.7%), acupuncture (1.5%) and orthomolecular medicine (0.2%). Women, Catholic, married of higher income and education were positively associated with utilization of therapies involving expenses. Complementary and alternative medicine is used by a significant number of those interviewed. Gender, religion, marital status, income and education were positively associated with utilization of complementary and alternative medicine. Access of those with less income and education could increase the utilization of the options that involve expenses.

Glutamine 57 at the complementary binding site face is a key determinant of morantel selectivity for {alpha}7 nicotinic receptors.

Science.gov (United States)

Bartos, Mariana; Price, Kerry L; Lummis, Sarah C R; Bouzat, Cecilia

2009-08-07

Nicotinic receptors (AChRs) play key roles in synaptic transmission. We explored activation of neuronal alpha7 and mammalian muscle AChRs by morantel and oxantel. Our results revealed a novel action of morantel as a high efficacy and more potent agonist than ACh of alpha7 receptors. The EC(50) for activation by morantel of both alpha7 and alpha7-5HT(3A) receptors is 7-fold lower than that determined for ACh. The minimum morantel concentration required to activate alpha7-5HT(3A) channels is 6-fold lower than that of ACh, and activation episodes are more prolonged than in the presence of ACh. By contrast, oxantel is a weak agonist of alpha7 and alpha7-5HT(3A), and both drugs are very low efficacy agonists of muscle AChRs. The replacement of Gln(57) in alpha7 by glycine, which is found in the equivalent position of the muscle AChR, decreases the efficacy for activation and turns morantel into a partial agonist. The reverse mutation in the muscle AChR (epsilonG57Q) increases 7-fold the efficacy of morantel. The mutations do not affect activation by ACh or oxantel, indicating that this position is selective for morantel. In silico studies show that the tetrahydropyrimidinyl group, common to both drugs, is close to Trp(149) of the principal face of the binding site, whereas the other cyclic group is proximal to Gln(57) of the complementary face in morantel but not in oxantel. Thus, position 57 at the complementary face is a key determinant of the high selectivity of morantel for alpha7. These results provide new information for further progress in drug design.

PRECONCEPTION AND PRENATAL DIAGNOSTIC TECHNIQUES ACT 1994 AND ITS MAIN ROLE TO CURB SEX DETERMINATION AND SEX SELECTION

OpenAIRE

Adv. Vaishali V. Waghmare; Dr. (Mrs) Hema Menon

2016-01-01

India has a male dominated culture where women are treated like a commodity and slave. Our Indian society gives preference only to the Son not to female because of which girls' child is not heartily welcomed and discrimination against girl child still prevails. Sex selective abortion is one of major issue in recent era in relation to violence against women under which the Ultrasonography machine plays an important role of sex detection. Main cause for sex selection are Patriarchal system, Do...

Sex differences in chemosensation: sensory or cognitive?

Directory of Open Access Journals (Sweden)

Kathrin eOhla

2013-09-01

Full Text Available Although the first sex-dependent differences for chemosensory processing were reported in the scientific literature over 60 years ago, the underlying mechanisms are still unknown. Generally, more pronounced sex-dependent differences are noted with increased task difficulty or with increased levels of intranasal irritation produced by the stimulus. Whether differences between the sexes arise from differences in chemosensory sensitivity of the two intranasal sensory systems involved or from differences in cognitive processing associated with emotional evaluation of the stimulants is still not known. We used simultaneous and complementary measures of electrophysiological (EEG, psychophysiological, and psychological responses to stimuli varying in intranasal irritation and oldorousness to investigate whether sex differences in the processing of intranasal irritation are mediated by varying sensitivity of the involved sensory systems or by differences in cognitive and/or emotional evaluation of the irritants. Women perceived all stimulants more irritating and they exhibited larger amplitudes of the late positive deflection of the event-related potential than men. No significant differences in sensory sensitivity, anxiety and arousal responses could be detected. Our findings suggest that men and women process intranasal irritation differently. Importantly, the differences cannot be explained by variation in sensory sensitivity to irritants, differences in anxiety or differences in physiological arousal. We propose that women allocate attention stronger to potentially noxious stimuli, which eventually causes differences in cognitive appraisal and subjective perception.

Complementary and alternative medicine in pregnancy: a survey of North Carolina certified nurse-midwives.

Science.gov (United States)

Allaire, A D; Moos, M K; Wells, S R

2000-01-01

To determine the prevalence and types of complementary and alternative medicine therapies used by certified nurse-midwives in North Carolina. Surveys were sent to all 120 licensed certified nurse-midwives in North Carolina requesting information concerning their recommendations for use of complementary and alternative medicine for their pregnant or postpartum patients. Eighty-two responses were received (68.3%). Seventy-seven (93.9%) reported recommending complementary and alternative medicine to their pregnant patients in the past year. Forty-seven (57.3%) reported recommending complementary and alternative medicine to more than 10% of patients. The percentage of nurse-midwives who recommended each type of complementary and alternative medicine was as follows: herbal therapy (73.2%), massage therapy (67.1%), chiropractic (57.3%), acupressure (52.4%), mind-body interventions (48.8%), aromatherapy (32.9%), homeopathy (30.5%), spiritual healing (23.2%), acupuncture (19.5%), and bioelectric or magnetic applications (14.6%). The 60 respondents who reported prescribing herbal therapies gave them for the following indications: nausea and vomiting, labor stimulation, perineal discomfort, lactation disorders, postpartum depression, preterm labor, postpartum hemorrhage, labor analgesia, and malpresentation. Complementary and alternative medicine, especially herbal therapy, is commonly prescribed to pregnant women by nurse-midwives in North Carolina.

Sexing sirenians: Validation of visual and molecular sex determination in both wild dugongs (Dugong dugon) and Florida manatees (Trichechus manatus latirostris)

Science.gov (United States)

Lanyon, J.M.; Sneath, H.L.; Ovenden, J.R.; Broderick, D.; Bonde, R.K.

2009-01-01

Sexing wild marine mammals that show little to no sexual dimorphism is challenging. For sirenians that are difficult to catch or approach closely, molecular sexing from tissue biopsies offers an alternative method to visual discrimination. This paper reports the results of a field study to validate the use of two sexing methods: (1) visual discrimination of sex vs (2) molecular sexing based on a multiplex PCR assay which amplifies the male-specific SRY gene and differentiates ZFX and ZFY gametologues. Skin samples from 628 dugongs (Dugong dugon) and 100 Florida manatees (Trichechus manatus latirostris) were analysed and assigned as male or female based on molecular sex. These individuals were also assigned a sex based on either direct observation of the genitalia and/or the association of the individual with a calf. Individuals of both species showed 93 to 96% congruence between visual and molecular sexing. For the remaining 4 to 7%, the discrepancies could be explained by human error. To mitigate this error rate, we recommend using both of these robust techniques, with routine inclusion of sex primers into microsatellite panels employed for identity, along with trained field observers and stringent sample handling.

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

The parasitoid wasp Nasonia vitripennis reproduces by haplodiploidy; males are haploid and females are diploid. Sex determination in Nasonia is not governed by complementary alleles at one or more sex loci. As in most other insects, the sex-determining pathway consists of the basal switch doublesex that is ...

Sex Determination from Fingerprint Ridge Density | Gungadin ...

African Journals Online (AJOL)

This study was conducted with an aim to establish a relationship between sex and fingerprint ridge density. The fingerprints were taken from 500 subjects (250 males and 250 females) in the age group of 18-60 years. After taking fingerprints, the ridges were counted in the upper portion of the radial border of each print for all ...

Analysis of the sex-determining region of the Y chromosome (SRY) in sex reversed patients: point-mutation in SRY causing sex-reversion in a 46,XY female

DEFF Research Database (Denmark)

Müller, Jørn; Schwartz, M; Skakkebaek, N E

1992-01-01

The first and essential step in normal sexual differentiation takes place during the 5th-6th week of gestation. The testis determining factor (TDF) directs the undifferentiated gonad into a testis, which secretes hormones responsible for normal male development. A new candidate for TDF has recently...... been reported, and it has been called the sex determining region of the Y (SRY). The hypothesis has been supported by the finding of XX individuals with SRY, and two females with 46,XY karyotype and a mutation in SRY. However, XX males without SRY has been reported, and the role of SRY still has...... to be determined. We have tested three human females with 46,XY karyotype and gonadal dysgenesis and two 46,XX males for the presence of SRY using the polymerase chain reaction and subsequent DNA sequencing. Both 46,XX males contained SRY, whereas one of the 46,XY females had suffered a point mutation in SRY...

The fate of W chromosomes in hybrids between wild silkmoths, Samia cynthia ssp.: no role in sex determination and reproduction

Czech Academy of Sciences Publication Activity Database

Yoshido, Atsuo; Marec, František; Sahara, K.

2016-01-01

Roč. 116, č. 5 (2016), s. 424-433 ISSN 0018-067X R&D Projects: GA ČR(CZ) GA14-22765S Grant - others:The European Union Seventh Framework Programme (FP7/2007-2013)(CZ) 316304 Program:FP7 Institutional support: RVO:60077344 Keywords : hybrids * sex chromosomes * sex determination Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.961, year: 2016

Did Lizards Follow Unique Pathways in Sex Chromosome Evolution?

Science.gov (United States)

Gleeson, Dianne; Georges, Arthur

2018-01-01

Reptiles show remarkable diversity in modes of reproduction and sex determination, including high variation in the morphology of sex chromosomes, ranging from homomorphic to highly heteromorphic. Additionally, the co-existence of genotypic sex determination (GSD) and temperature-dependent sex determination (TSD) within and among sister clades makes this group an attractive model to study and understand the evolution of sex chromosomes. This is particularly so with Lizards (Order Squamata) which, among reptiles, show extraordinary morphological diversity. They also show no particular pattern of sex chromosome degeneration of the kind observed in mammals, birds and or even in snakes. We therefore speculate that sex determination sensu sex chromosome evolution is labile and rapid and largely follows independent trajectories within lizards. Here, we review the current knowledge on the evolution of sex chromosomes in lizards and discuss how sex chromosome evolution within that group differs from other amniote taxa, facilitating unique evolutionary pathways. PMID:29751579

Did Lizards Follow Unique Pathways in Sex Chromosome Evolution?

Directory of Open Access Journals (Sweden)

Shayer Mahmood Ibney Alam

2018-05-01

Full Text Available Reptiles show remarkable diversity in modes of reproduction and sex determination, including high variation in the morphology of sex chromosomes, ranging from homomorphic to highly heteromorphic. Additionally, the co-existence of genotypic sex determination (GSD and temperature-dependent sex determination (TSD within and among sister clades makes this group an attractive model to study and understand the evolution of sex chromosomes. This is particularly so with Lizards (Order Squamata which, among reptiles, show extraordinary morphological diversity. They also show no particular pattern of sex chromosome degeneration of the kind observed in mammals, birds and or even in snakes. We therefore speculate that sex determination sensu sex chromosome evolution is labile and rapid and largely follows independent trajectories within lizards. Here, we review the current knowledge on the evolution of sex chromosomes in lizards and discuss how sex chromosome evolution within that group differs from other amniote taxa, facilitating unique evolutionary pathways.

Complementary Feeding: Review of Recommendations, Feeding Practices and Adequacy of Homemade Complementary Food Preparations in Developing Countries – lessons from Ethiopia

Directory of Open Access Journals (Sweden)

Motuma A Abeshu

2016-10-01

Full Text Available Breastfeeding provides the ideal food during the first 6 months of life. Complementary feeding is the process starting when breast milk alone is no longer sufficient, the target age being between 6 to 23 months. The gap between nutritional requirement and amount obtained from breast milk increases with age. For energy, 200kcal, 300kcal and 550kcal per day is expected to be covered by complementary foods at 6-8, 9-11 and 12-23 months, respectively. In addition, the complementary foods must provide relatively large proportions of micronutrients such as: iron, zinc, phosphorus, magnesium, calcium and vitamin B6. In several parts of the developing world, complementary feeding continues as a challenge to good nutrition in children. In Ethiopia, only 4.2% of breastfed children of 6–23 months of age have a minimum acceptable diet. The gaps are mostly attributed to either poor dietary quality or poor feeding practices, if not both. Commercial fortified foods are often beyond the reach of the poor. Thus, homemade complementary foods remain commonly used. However, unfortified complementary foods that are predominantly plant-based provide insufficient amounts of key nutrients (particularly iron, zinc and calcium during the age of 6 – 23 months even, when based on an improved recipe. This review thus assessed complementary feeding practice and recommendation and reviewed the level of adequacy of homemade complementary foods.

Same sex marriage and the perceived assault on opposite sex marriage.

Science.gov (United States)

Dinno, Alexis; Whitney, Chelsea

2013-01-01

Marriage benefits both individuals and societies, and is a fundamental determinant of health. Until recently same sex couples have been excluded from legally recognized marriage in the United States. Recent debate around legalization of same sex marriage has highlighted for anti-same sex marriage advocates and policy makers a concern that allowing same sex couples to marry will lead to a decrease in opposite sex marriages. Our objective is to model state trends in opposite sex marriage rates by implementation of same sex marriages and other same sex unions. Marriage data were obtained for all fifty states plus the District of Columbia from 1989 through 2009. As these marriage rates are non-stationary, a generalized error correction model was used to estimate long run and short run effects of same sex marriages and strong and weak same sex unions on rates of opposite sex marriage. We found that there were no significant long-run or short run effects of same sex marriages or of strong or weak same sex unions on rates of opposite sex marriage. A deleterious effect on rates of opposite sex marriage has been argued to be a motivating factor for both the withholding and the elimination of existing rights of same sex couples to marry by policy makers-including presiding justices of current litigation over the rights of same sex couples to legally marry. Such claims do not appear credible in the face of the existing evidence, and we conclude that rates of opposite sex marriages are not affected by legalization of same sex civil unions or same sex marriages.

Same Sex Marriage and the Perceived Assault on Opposite Sex Marriage

Science.gov (United States)

Dinno, Alexis; Whitney, Chelsea

2013-01-01

Background Marriage benefits both individuals and societies, and is a fundamental determinant of health. Until recently same sex couples have been excluded from legally recognized marriage in the United States. Recent debate around legalization of same sex marriage has highlighted for anti-same sex marriage advocates and policy makers a concern that allowing same sex couples to marry will lead to a decrease in opposite sex marriages. Our objective is to model state trends in opposite sex marriage rates by implementation of same sex marriages and other same sex unions. Methods and Findings Marriage data were obtained for all fifty states plus the District of Columbia from 1989 through 2009. As these marriage rates are non-stationary, a generalized error correction model was used to estimate long run and short run effects of same sex marriages and strong and weak same sex unions on rates of opposite sex marriage. We found that there were no significant long-run or short run effects of same sex marriages or of strong or weak same sex unions on rates of opposite sex marriage. Conclusion A deleterious effect on rates of opposite sex marriage has been argued to be a motivating factor for both the withholding and the elimination of existing rights of same sex couples to marry by policy makers–including presiding justices of current litigation over the rights of same sex couples to legally marry. Such claims do not appear credible in the face of the existing evidence, and we conclude that rates of opposite sex marriages are not affected by legalization of same sex civil unions or same sex marriages. PMID:23776536

Complementary and alternative interventions in atopic dermatitis.

Science.gov (United States)

Lee, Joohee; Bielory, Leonard

2010-08-01

The burden of atopic diseases, including atopic dermatitis (AD), is significant and far-reaching. In addition to cost of care and therapies, it affects the quality of life for those affected as well as their caretakers. Complementary and alternative therapies are commonly used because of concerns about potential adverse effects of conventional therapies and frustration with the lack of response to prescribed medications, be it due to the severity of the AD or the lack of appropriate regular use. Despite the promising results reported with various herbal medicines and biologic products, the clinical efficacy of such alternative therapies remains to be determined. Physicians need to be educated about alternative therapies and discuss benefits and potential adverse effects or limitations with patients. A systematic approach and awareness of reputable and easily accessible resources are helpful in dealing with complementary and alternative medicine (CAM). The use of CAM interventions is common among individuals with AD. Epidemiologic data have been a motivating drive for better elucidation of the efficacy of CAM interventions for allergic disease. Herbal medicines and biologics for AD treatment and, more recently, prevention comprise a major area of clinical investigation. Potential mechanisms of therapeutic effect elucidated by animal models and human clinical studies implicate modulation of TH2-type allergic inflammation and induction of immune tolerance. Population-based research regarding the use of CAM for allergic diseases underscores the increasing challenge for care providers with respect to identifying CAM use and ensuring safe use of allopathic and complementary medicines in disease management. Copyright 2010. Published by Elsevier Inc.

The Wright stuff: reimagining path analysis reveals novel components of the sex determination hierarchy in Drosophila melanogaster.

Science.gov (United States)

Fear, Justin M; Arbeitman, Michelle N; Salomon, Matthew P; Dalton, Justin E; Tower, John; Nuzhdin, Sergey V; McIntyre, Lauren M

2015-09-04

The Drosophila sex determination hierarchy is a classic example of a transcriptional regulatory hierarchy, with sex-specific isoforms regulating morphology and behavior. We use a structural equation modeling approach, leveraging natural genetic variation from two studies on Drosophila female head tissues--DSPR collection (596 F1-hybrids from crosses between DSPR sub-populations) and CEGS population (75 F1-hybrids from crosses between DGRP/Winters lines to a reference strain w1118)--to expand understanding of the sex hierarchy gene regulatory network (GRN). This approach is completely generalizable to any natural population, including humans. We expanded the sex hierarchy GRN adding novel links among genes, including a link from fruitless (fru) to Sex-lethal (Sxl) identified in both populations. This link is further supported by the presence of fru binding sites in the Sxl locus. 754 candidate genes were added to the pathway, including the splicing factors male-specific lethal 2 and Rm62 as downstream targets of Sxl which are well-supported links in males. Independent studies of doublesex and transformer mutants support many additions, including evidence for a link between the sex hierarchy and metabolism, via Insulin-like receptor. The genes added in the CEGS population were enriched for genes with sex-biased splicing and components of the spliceosome. A common goal of molecular biologists is to expand understanding about regulatory interactions among genes. Using natural alleles we can not only identify novel relationships, but using supervised approaches can order genes into a regulatory hierarchy. Combining these results with independent large effect mutation studies, allows clear candidates for detailed molecular follow-up to emerge.

Gender preference and awareness regarding sex determination among antenatal mothers attending a medical college of eastern India.

Science.gov (United States)

Yasmin, Shamima; Mukherjee, Anindya; Manna, Nirmalya; Baur, Baijayanti; Datta, Mousumi; Sau, Manabendra; Roy, Manidipa; Dasgupta, Samir

2013-06-01

There are many women "missing" due to an unfavourable sex ratio in India, which has strong patriarchal norms and a preference for sons. Female gender discrimination has been reported in health care, nutrition, education, and resource allocation due to man-made norms, religious beliefs, and recently by ultrasonography resulting in lowered sex ratio. The present study attempts to find out the level of awareness regarding sex determination and to explore preference of gender and factors associated among antenatal mothers attending a medical college in eastern India. Interviews were done by predesigned pretested proforma over 6 months. The data were analysed by SPSS 16.0 software for proportions with chi-squared tests and binary logistic regression analysis. Most women who were multigravida did not know about contraceptives; 1.8% of mothers knew the sex of the fetus in present pregnancy while another 34.7% expressed willingness; 13.6% knew of a place which could tell sex of the fetus beforehand; 55.6% expressed their preference of sex of the baby for present pregnancy while 50.6% of their husbands had gender preference. Gender preference was significantly high in subjects with: lower socioeconomic status (p=0.011); lower level of education of mother (p=0.047) and husband (p=0.0001); multigravida (p=0.002); presence of living children (p=0.0001); and husband having preference of sex of baby (p=0.0001). Parental education, socioeconomic background, and number of living issues were the main predictors for gender preference. Awareness regarding gender preference and related law and parental counselling to avoid gender preference with adoption of small family norm is recommended.

Turnover of sex chromosomes induced by sexual conflict

NARCIS (Netherlands)

van Doorn, G. S.; Kirkpatrick, Mark

2007-01-01

Sex-determination genes are among the most fluid features of the genome in many groups of animals(1,2). In some taxa the master sex-determining gene moves frequently between chromosomes, whereas in other taxa different genes have been recruited to determine the sex of the zygotes. There is a well

MODERN COMPLEMENTARY FOODS IN THE PREVENTION OF ALLERGIC DISEASES: PROSPECTIVE STUDY RESULTS

Directory of Open Access Journals (Sweden)

Т. E. Borovik

2014-01-01

Full Text Available Background: Rate allergenic properties of the complementary food line based on grains, fruits/vegetables and meat in the diet of infants (0–1 years old. Methods: The study included children aged 4–6 months with natural, mixed or artificial feeding, who had not received any complementary food before. The children were almost healthy or had a burdened allergic history. Complementary foods (porridge, vegetable puree, meat puree and fruit puree were administered basing on an individual plan depending on age, nutritional status and nature of feces. Tolerability of products and dynamics of mass-height and laboratory parameters were evaluated. At the beginning and at the end of the study, capillary blood was taken to determine the content of hemoglobin in red blood cells (MCH, the equivalent of hemoglobin in reticulocytes (RetHe, iron, ferritin, prealbumin, and specific E class immunoglobulin (IgE to the proteins in cow's and goat milk, apples, pears, prunes, zucchini, broccoli, cauliflower, rice, maize, buckwheat, turkey meat, and rabbit meat (quantitative allergy diagnostics using an express method. In addition, a scatological study was performed. Results: 60 healthy children received complementary foods based on grains, fruits/vegetables and meat on a step-by-step basis. The level of specific IgE to food allergens in all children under the study was within normal range (0–135 IU/ml both initially and after the administration of all the complementary foods studied. Conclusion: The investigated complementary foods have a low sensitizing potential, including in children with a burdened allergic history. This allows us to describe them as hypoallergenic products.

Detraditionalisation, gender and alternative and complementary medicines.

Science.gov (United States)

Sointu, Eeva

2011-03-01

This article is premised on the importance of locating the appeal and meaning of alternative and complementary medicines in the context of gendered identities. I argue that the discourse of wellbeing--captured in many alternative and complementary health practices--is congruent with culturally prevalent ideals of self-fulfilling, authentic, unique and self-responsible subjectivity. The discourse of wellbeing places the self at the centre, thus providing a contrast with traditional ideas of other-directed and caring femininity. As such, involvement in alternative and complementary medicines is entwined with a negotiation of shifting femininities in detraditionalising societies. Simultaneously, many alternative and complementary health practices readily tap into and reproduce traditional representations of caring femininity. It is through an emphasis on emotional honesty and intimacy that the discourse of wellbeing also captures a challenge to traditional ideas of masculinity. Expectations and experiences relating to gender add a further level of complexity to the meaningfulness and therapeutic value of alternative and complementary medicines and underlie the gender difference in the utilisation of holistic health practices. I draw on data from a qualitative study with 44, primarily white, middle-class users and practitioners of varied alternative and complementary medicines in the UK. © 2010 The Author. Sociology of Health & Illness © 2010 Foundation for the Sociology of Health & Illness/Blackwell Publishing Ltd.

Criminal Profiles of Violent Juvenile Sex and Violent Juvenile Non-Sex Offenders: An Explorative Longitudinal Study

Science.gov (United States)

van Wijk, Anton Ph.; Mali, Bas R. F.; Bullens, Ruud A. R.; Vermeiren, Robert R.

2007-01-01

Few studies have longitudinally investigated the criminal profiles of violent juvenile sex and violent juvenile non-sex offenders. To make up for this lack, this study used police records of juveniles to determine the nature of the criminal profiles of violent sex offenders (n = 226) and violent non-sex offenders (n = 4,130). All offenders…

Integrative Medicine and Complementary and Alternative Therapies

Science.gov (United States)

... complementary therapies with your healthcare team: Are there complementary therapies that you would recommend? What research is available about this therapy’s safety and effectiveness? What are the benefits and risks of this ...

African Journal of Traditional, Complementary and Alternative ...

African Journals Online (AJOL)

African Journal of Traditional, Complementary and Alternative Medicines: Advanced Search. Journal Home > African Journal of Traditional, Complementary and Alternative Medicines: Advanced Search. Log in or Register to get access to full text downloads.

Inherited XX sex reversal originating from wild medaka populations.

Science.gov (United States)

Shinomiya, A; Otake, H; Hamaguchi, S; Sakaizumi, M

2010-11-01

The teleost fish, medaka (Oryzias latipes), has an XX/XY sex-determining mechanism. A Y-linked DM domain gene, DMY, has been isolated by positional cloning as the sex-determining gene in this species. Previously, we conducted a field survey of genotypic sex and found that approximately 1% of wild medaka are sex-reversed (XX males and XY females). Here, we performed genetic analyses of nine spontaneous XX sex-reversed males to elucidate its genetic basis. In all cases, the F(1) progeny were all females, whereas XX males reappeared in the backcross (BC) progeny, suggesting that XX sex reversal is a recessive trait. Although the incidences of sex reversal in the BC progeny were mostly low, 40% were males derived from one XX male. We performed linkage analysis using 55 BC males and located a single major factor, sda-1 (sex-determining autosomal factor-1), controlling sex reversal in an autosomal linkage group. Thus, genes involved in the sex-determining pathway can be isolated from spontaneous mutants in wild populations.

Sexual economics: sex as female resource for social exchange in heterosexual interactions.

Science.gov (United States)

Baumeister, Roy F; Vohs, Kathleen D

2004-01-01

A heterosexual community can be analyzed as a marketplace in which men seek to acquire sex from women by offering other resources in exchange. Societies will therefore define gender roles as if women are sellers and men buyers of sex. Societies will endow female sexuality, but not male sexuality, with value (as in virginity, fidelity, chastity). The sexual activities of different couples are loosely interrelated by a marketplace, instead of being fully separate or private, and each couple's decisions may be influenced by market conditions. Economic principles suggest that the price of sex will depend on supply and demand, competition among sellers, variations in product, collusion among sellers, and other factors. Research findings show gender asymmetries (reflecting the complementary economic roles) in prostitution, courtship, infidelity and divorce, female competition, the sexual revolution and changing norms, unequal status between partners, cultural suppression of female sexuality, abusive relationships, rape, and sexual attitudes.

Expression profiles for six zebrafish genes during gonadal sex differentiation

DEFF Research Database (Denmark)

Jørgensen, Anne; Morthorst, Jane Ebsen; Andersen, Ole

2008-01-01

BACKGROUND: The mechanism of sex determination in zebrafish is largely unknown and neither sex chromosomes nor a sex-determining gene have been identified. This indicates that sex determination in zebrafish is mediated by genetic signals from autosomal genes. The aim of this study was to determine...... the precise timing of expression of six genes previously suggested to be associated with sex differentiation in zebrafish. The current study investigates the expression of all six genes in the same individual fish with extensive sampling dates during sex determination and -differentiation. RESULTS......: In the present study, we have used quantitative real-time PCR to investigate the expression of ar, sox9a, dmrt1, fig alpha, cyp19a1a and cyp19a1b during the expected sex determination and gonadal sex differentiation period. The expression of the genes expected to be high in males (ar, sox9a and dmrt1a) and high...

Perception of risk and communication among conventional and complementary health care providers involving cancer patients' use of complementary therapies: a literature review.

Science.gov (United States)

Stub, Trine; Quandt, Sara A; Arcury, Thomas A; Sandberg, Joanne C; Kristoffersen, Agnete E; Musial, Frauke; Salamonsen, Anita

2016-09-08

Communication between different health care providers (conventional and complementary) and cancer patients about their use of complementary therapies affects the health and safety of the patients. The aim of this study was to examine the qualitative research literature on the perception of and communication about the risk of complementary therapies between different health care providers and cancer patients. Systematic searches in six medical databases covering literature from 2000 to 2015 were performed. The studies were accessed according to the level of evidence and summarized into different risk situations. Qualitative content analysis was used to analyze the text data, and the codes were defined before and during the data analysis. Twenty-nine papers were included in the primary analysis and five main themes were identified and discussed. The main risk situations identified were 1. Differences in treatment concepts and philosophical values among complementary and conventional health care providers. 2. Adverse effects from complementary products and herbs due to their contamination/toxicity and interactions with conventional cancer treatment. 3. Health care physicians and oncologists find it difficult to recommend many complementary modalities due to the lack of scientific evidence for their effect. 4. Lack of knowledge and information about complementary and conventional cancer treatments among different health care providers. The risk of consuming herbs and products containing high level of toxins is a considerable threat to patient safety (direct risk). At the same time, the lack of scientific evidence of effect for many complementary therapies and differences in treatment philosophy among complementary and conventional health care providers potentially hinder effective communication about these threats with mutual patients (indirect risk). As such, indirect risk may pose an additional risk to patients who want to combine complementary therapies with

Loss of mitogen-activated protein kinase kinase kinase 4 (MAP3K4 reveals a requirement for MAPK signalling in mouse sex determination.

Directory of Open Access Journals (Sweden)

Debora Bogani

2009-09-01

Full Text Available Sex determination in mammals is controlled by the presence or absence of the Y-linked gene SRY. In the developing male (XY gonad, sex-determining region of the Y (SRY protein acts to up-regulate expression of the related gene, SOX9, a transcriptional regulator that in turn initiates a downstream pathway of testis development, whilst also suppressing ovary development. Despite the requirement for a number of transcription factors and secreted signalling molecules in sex determination, intracellular signalling components functioning in this process have not been defined. Here we report a role for the phylogenetically ancient mitogen-activated protein kinase (MAPK signalling pathway in mouse sex determination. Using a forward genetic screen, we identified the recessive boygirl (byg mutation. On the C57BL/6J background, embryos homozygous for byg exhibit consistent XY gonadal sex reversal. The byg mutation is an A to T transversion causing a premature stop codon in the gene encoding MAP3K4 (also known as MEKK4, a mitogen-activated protein kinase kinase kinase. Analysis of XY byg/byg gonads at 11.5 d post coitum reveals a growth deficit and a failure to support mesonephric cell migration, both early cellular processes normally associated with testis development. Expression analysis of mutant XY gonads at the same stage also reveals a dramatic reduction in Sox9 and, crucially, Sry at the transcript and protein levels. Moreover, we describe experiments showing the presence of activated MKK4, a direct target of MAP3K4, and activated p38 in the coelomic region of the XY gonad at 11.5 d post coitum, establishing a link between MAPK signalling in proliferating gonadal somatic cells and regulation of Sry expression. Finally, we provide evidence that haploinsufficiency for Map3k4 accounts for T-associated sex reversal (Tas. These data demonstrate that MAP3K4-dependent signalling events are required for normal expression of Sry during testis development, and

Loss of Mitogen-Activated Protein Kinase Kinase Kinase 4 (MAP3K4) Reveals a Requirement for MAPK Signalling in Mouse Sex Determination

Science.gov (United States)

Bogani, Debora; Siggers, Pam; Brixey, Rachel; Warr, Nick; Beddow, Sarah; Edwards, Jessica; Williams, Debbie; Wilhelm, Dagmar; Koopman, Peter; Flavell, Richard A.; Chi, Hongbo; Ostrer, Harry; Wells, Sara; Cheeseman, Michael; Greenfield, Andy

2009-01-01

Sex determination in mammals is controlled by the presence or absence of the Y-linked gene SRY. In the developing male (XY) gonad, sex-determining region of the Y (SRY) protein acts to up-regulate expression of the related gene, SOX9, a transcriptional regulator that in turn initiates a downstream pathway of testis development, whilst also suppressing ovary development. Despite the requirement for a number of transcription factors and secreted signalling molecules in sex determination, intracellular signalling components functioning in this process have not been defined. Here we report a role for the phylogenetically ancient mitogen-activated protein kinase (MAPK) signalling pathway in mouse sex determination. Using a forward genetic screen, we identified the recessive boygirl (byg) mutation. On the C57BL/6J background, embryos homozygous for byg exhibit consistent XY gonadal sex reversal. The byg mutation is an A to T transversion causing a premature stop codon in the gene encoding MAP3K4 (also known as MEKK4), a mitogen-activated protein kinase kinase kinase. Analysis of XY byg/byg gonads at 11.5 d post coitum reveals a growth deficit and a failure to support mesonephric cell migration, both early cellular processes normally associated with testis development. Expression analysis of mutant XY gonads at the same stage also reveals a dramatic reduction in Sox9 and, crucially, Sry at the transcript and protein levels. Moreover, we describe experiments showing the presence of activated MKK4, a direct target of MAP3K4, and activated p38 in the coelomic region of the XY gonad at 11.5 d post coitum, establishing a link between MAPK signalling in proliferating gonadal somatic cells and regulation of Sry expression. Finally, we provide evidence that haploinsufficiency for Map3k4 accounts for T-associated sex reversal (Tas). These data demonstrate that MAP3K4-dependent signalling events are required for normal expression of Sry during testis development, and create a novel

Mayfly and fish species identification and sex determination in bleak (Alburnus alburnus) by MALDI-TOF mass spectrometry.

Science.gov (United States)

Maasz, G; Takács, P; Boda, P; Varbiro, G; Pirger, Z

2017-12-01

Besides food quality control of fish or cephalopods, the novel mass spectrometry (MS) approaches could be effective and beneficial methods for the investigation of biodiversity in ecological research. Our aims were to verify the applicability of MALDI-TOF MS in the rapid identification of closely related species, and to further develop it for sex determination in phenotypically similar fish focusing on the low mass range. For MALDI-TOF MS spectra analysis, ClinProTools software was applied, but our observed classification was also confirmed by Self Organizing Map. For verifying the wide applicability of the method, brains from invertebrate and vertebrate species were used in order to detect the species related markers from two mayflies and eight fish as well as sex-related markers within bleak. Seven Ephemera larvae and sixty-one fish species related markers were observed and nineteen sex-related markers were identified in bleak. Similar patterns were observed between the individuals within one species. In contrast, there were markedly diverse patterns between the different species and sexes visualized by SOMs. Two different Ephemera species and male or female fish were identified with 100% accuracy. The various fish species were classified into 8 species with a high level of accuracy (96.2%). Based on MS data, dendrogram was generated from different fish species by using ClinProTools software. This MS-based dendrogram shows relatively high correspondence with the phylogenetic relationships of both the studied species and orders. In summary, MALDI-TOF MS provides a cheap, reliable, sensitive and fast identification tool for researchers in the case of closely related species using mass spectra acquired in a low mass range to define specific molecular profiles. Moreover, we presented evidence for the first time for determination of sex within one fish species by using this method. We conclude that it is a powerful tool that can revolutionize ecological and

Gonad Transcriptome Analysis of the Pacific Oyster Crassostrea gigas Identifies Potential Genes Regulating the Sex Determination and Differentiation Process.

Science.gov (United States)

Yue, Chenyang; Li, Qi; Yu, Hong

2018-04-01

The Pacific oyster Crassostrea gigas is a commercially important bivalve in aquaculture worldwide. C. gigas has a fascinating sexual reproduction system consisting of dioecism, sex change, and occasional hermaphroditism, while knowledge of the molecular mechanisms of sex determination and differentiation is still limited. In this study, the transcriptomes of male and female gonads at different gametogenesis stages were characterized by RNA-seq. Hierarchical clustering based on genes differentially expressed revealed that 1269 genes were expressed specifically in female gonads and 817 genes were expressed increasingly over the course of spermatogenesis. Besides, we identified two and one gene modules related to female and male gonad development, respectively, using weighted gene correlation network analysis (WGCNA). Interestingly, GO and KEGG enrichment analysis showed that neurotransmitter-related terms were significantly enriched in genes related to ovary development, suggesting that the neurotransmitters were likely to regulate female sex differentiation. In addition, two hub genes related to testis development, lncRNA LOC105321313 and Cg-Sh3kbp1, and one hub gene related to ovary development, Cg-Malrd1-like, were firstly investigated. This study points out the role of neurotransmitter and non-coding RNA regulation during gonad development and produces lists of novel relevant candidate genes for further studies. All of these provided valuable information to understand the molecular mechanisms of C. gigas sex determination and differentiation.

Sex reversal in vertebrates

OpenAIRE

2016-01-01

This special topic issue of Sexual Development gives an overview of sex reversal in vertebrates, from fishes naturally changing their sex, to rodents escaping the mammalian SRY-determining system. It offers eight up-to-date reviews on specific subjects in sex reversal, considering fishes, amphibians, reptiles, birds, marsupials, and placental mammals, including humans. The broad scope of represented animals makes this ideal for students and researchers, especially those interested in the...

Stress and sex: does cortisol mediate sex change in fish?

Science.gov (United States)

Goikoetxea, Alexander; Todd, Erica V; Gemmell, Neil J

2017-12-01

Cortisol is the main glucocorticoid (GC) in fish and the hormone most directly associated with stress. Recent research suggests that this hormone may act as a key factor linking social environmental stimuli and the onset of sex change by initiating a shift in steroidogenesis from estrogens to androgens. For many teleost fish, sex change occurs as a usual part of the life cycle. Changing sex is known to enhance the lifetime reproductive success of these fish and the modifications involved (behavioral, gonadal and morphological) are well studied. However, the exact mechanism behind the transduction of the environmental signals into the molecular cascade that underlies this singular process remains largely unknown. We here synthesize current knowledge regarding the role of cortisol in teleost sex change with a focus on two well-described transformations: temperature-induced masculinization and socially regulated sex change. Three non-mutually exclusive pathways are considered when describing the potential role of cortisol in mediating teleost sex change: cross-talk between GC and androgen pathways, inhibition of aromatase expression and upregulation of amh (the gene encoding anti-Müllerian hormone). We anticipate that understanding the role of cortisol in the initial stages of sex change will further improve our understanding of sex determination and differentiation across vertebrates, and may lead to new tools to control fish sex ratios in aquaculture. © 2017 Society for Reproduction and Fertility.

A novel pseudo-complementary PNA G-C base pair

DEFF Research Database (Denmark)

Olsen, Anne G.; Dahl, Otto; Petersen, Asger Bjørn

2011-01-01

Pseudo-complementary oligonucleotide analogues and mimics provide novel opportunities for targeting duplex structures in RNA and DNA. Previously, a pseudo-complementary A-T base pair has been introduced. Towards sequence unrestricted targeting, a pseudo-complementary G-C base pair consisting...

A study to review sex ratio at birth and analyze preferences for the sex of the unborn.

Science.gov (United States)

Warade, Yugali; Balsarkar, Geetha; Bandekar, Pooja

2014-02-01

(1) To study the status of sex ratio at birth with increasing birth order, (2) To ascertain the relationship of declining sex ratio with respect to socio demographic factors. (3) To study outlook of patient towards sex preference, willingness to determine sex of the fetus, wish to terminate the pregnancy in case of unwanted sex of the baby. This is the retrospective study done in the Department of Obstetrics and Gynaecology, Nowrosjee Wadia Maternity Hospital, Parel, Mumbai. The data was collected from the records maintained in Medical Record Department from January 2007 to December 2012 and were studied to determine the sex ratio as well as its relationship with the increasing parity. 95 % confidence interval for the sex ratios was calculated. Average sex ratio of 6 years was 908 females per 1,000 males. Sex ratio was 972 females per 1,000 males in primi para, which decreased to 879 females per 1,000 males in second para, further reduced to 784 females per 1,000 males in third para and 864 females per 1,000 males in fourth para. The 'sex ratio at birth', defined as the number of girls born for every 1,000 boys born, is a more accurate and refined indicator of the extent of prenatal sex selection.

Reconfigurable Complementary Logic Circuits with Ambipolar Organic Transistors.

Science.gov (United States)

Yoo, Hocheon; Ghittorelli, Matteo; Smits, Edsger C P; Gelinck, Gerwin H; Lee, Han-Koo; Torricelli, Fabrizio; Kim, Jae-Joon

2016-10-20

Ambipolar organic electronics offer great potential for simple and low-cost fabrication of complementary logic circuits on large-area and mechanically flexible substrates. Ambipolar transistors are ideal candidates for the simple and low-cost development of complementary logic circuits since they can operate as n-type and p-type transistors. Nevertheless, the experimental demonstration of ambipolar organic complementary circuits is limited to inverters. The control of the transistor polarity is crucial for proper circuit operation. Novel gating techniques enable to control the transistor polarity but result in dramatically reduced performances. Here we show high-performance non-planar ambipolar organic transistors with electrical control of the polarity and orders of magnitude higher performances with respect to state-of-art split-gate ambipolar transistors. Electrically reconfigurable complementary logic gates based on ambipolar organic transistors are experimentally demonstrated, thus opening up new opportunities for ambipolar organic complementary electronics.

Office of Cancer Complementary and Alternative Medicine

Science.gov (United States)

... C Research. Information. Outreach. The Office of Cancer Complementary and Alternative Medicine (OCCAM) was established in October 1998 to coordinate ... National Cancer Institute (NCI) in the arena of complementary and alternative medicine (CAM). More about us. CAM at the NCI ...

Conserved regulatory modules in the Sox9 testis-specific enhancer predict roles for SOX, TCF/LEF, Forkhead, DMRT, and GATA proteins in vertebrate sex determination.

Science.gov (United States)

Bagheri-Fam, Stefan; Sinclair, Andrew H; Koopman, Peter; Harley, Vincent R

2010-03-01

While the primary sex determining switch varies between vertebrate species, a key downstream event in testicular development, namely the male-specific up-regulation of Sox9, is conserved. To date, only two sex determining switch genes have been identified, Sry in mammals and the Dmrt1-related gene Dmy (Dmrt1bY) in the medaka fish Oryzias latipes. In mice, Sox9 expression is evidently up-regulated by SRY and maintained by SOX9 both of which directly activate the core 1.3 kb testis-specific enhancer of Sox9 (TESCO). How Sox9 expression is up-regulated and maintained in species without Sry (i.e. non-mammalian species) is not understood. In this study, we have undertaken an in-depth comparative genomics approach and show that TESCO contains an evolutionarily conserved region (ECR) of 180 bp which is present in marsupials, monotremes, birds, reptiles and amphibians. The ECR contains highly conserved modules that predict regulatory roles for SOX, TCF/LEF, Forkhead, DMRT, and GATA proteins in vertebrate sex determination/differentiation. Our data suggest that tetrapods share common aspects of Sox9 regulation in the testis, despite having different sex determining switch mechanisms. They also suggest that Sox9 autoregulation is an ancient mechanism shared by all tetrapods, raising the possibility that in mammals, SRY evolved by mimicking this regulation. The validation of ECR regulatory sequences conserved from human to frogs will provide new insights into vertebrate sex determination. Copyright 2009 Elsevier Ltd. All rights reserved.

The behavioural consequences of sex reversal in dragons

Science.gov (United States)

Li, Hong; Holleley, Clare E.; Elphick, Melanie; Georges, Arthur

2016-01-01

Sex differences in morphology, physiology, and behaviour are caused by sex-linked genes, as well as by circulating sex-steroid levels. Thus, a shift from genotypic to environmental sex determination may create an organism that exhibits a mixture of male-like and female-like traits. We studied a lizard species (Central Bearded Dragon, Pogona vitticeps), in which the high-temperature incubation of eggs transforms genetically male individuals into functional females. Although they are reproductively female, sex-reversed dragons (individuals with ZZ genotype reversed to female phenotype) resemble genetic males rather than females in morphology (relative tail length), general behaviour (boldness and activity level), and thermoregulatory tactics. Indeed, sex-reversed ‘females’ are more male-like in some behavioural traits than are genetic males. This novel phenotype may impose strong selection on the frequency of sex reversal within natural populations, facilitating rapid shifts in sex-determining systems. A single period of high incubation temperatures (generating thermally induced sex reversal) can produce functionally female individuals with male-like (or novel) traits that enhance individual fitness, allowing the new temperature-dependent sex-determining system to rapidly replace the previous genetically based one.

Discovering complementary colors from the perspective of steam education

Science.gov (United States)

Karabey, Burak; Yigit Koyunkaya, Melike; Enginoglu, Turan; Yurumezoglu, Kemal

2018-05-01

This study explored the theory and applications of complementary colors using a technology-based activity designed from the perspective of STEAM education. Complementary colors and their areas of use were examined from the perspective of physics, mathematics and art, respectively. The study, which benefits from technology, makes the theory of complementary colors accessible to all through practical applications and provides a multidisciplinary, integrated and innovative technique of teaching the subject of colors, which could be used to teach complementary colors.

Distinct sperm nucleus behaviors between genotypic and temperature-dependent sex determination males are associated with replication and expression-related pathways in a gynogenetic fish.

Science.gov (United States)

Zhu, Yao-Jun; Li, Xi-Yin; Zhang, Jun; Li, Zhi; Ding, Miao; Zhang, Xiao-Juan; Zhou, Li; Gui, Jian-Fang

2018-06-05

Coexistence and transition of diverse sex determination strategies have been revealed in some ectothermic species, but the variation between males caused by different sex determination strategies and the underlying mechanism remain unclear. Here, we used the gynogenetic gibel carp (Carassius gibelio) with both genotypic sex determination (GSD) and temperature-dependent sex determination (TSD) strategies to illustrate this issue. We found out that males of GSD and TSD in gibel carp had similar morphology, testicular histology, sperm structure and sperm vitality. However, when maternal individuals were mated with males of GSD, sperm nucleus swelling and fusing with the female pronucleus were observed in the fertilized eggs. On the contrary, when maternal individuals were mated with males of TSD, sperm nucleus remained in the condensed status throughout the whole process. Subsequently, semen proteomics analysis unveiled that DNA replication and gene expression-related pathways were inhibited in the sperm from males of TSD compared to males of GSD, and most differentially expressed proteins associated with DNA replication, transcription and translation were down-regulated. Moreover, via BrdU incorporation and immunofluorescence detection, male nucleus replication was revealed to be present in the fertilized eggs by the sperm from males of GSD, but absent in the fertilized eggs by the sperm from males of TSD. These findings indicate that DNA replication and gene expression-related pathways are associated with the distinct sperm nucleus development behaviors in fertilized eggs in response to the sperm from males of GSD and TSD. And this study is the first attempt to screen the differences between males determined via GSD and TSD in gynogenetic species, which might give a hint for understanding evolutionary adaption of diverse sex determination mechanisms in unisexual vertebrates.

Sex-related and non-sex-related comorbidity subtypes of tic disorders: a latent class approach.

Science.gov (United States)

Rodgers, S; Müller, M; Kawohl, W; Knöpfli, D; Rössler, W; Castelao, E; Preisig, M; Ajdacic-Gross, V

2014-05-01

Recent evidence suggests that there may be more than one Gilles de la Tourette syndrome (GTS)/tic disorder phenotype. However, little is known about the common patterns of these GTS/tic disorder-related comorbidities. In addition, sex-specific phenomenological data of GTS/tic disorder-affected adults are rare. Therefore, this community-based study used latent class analyses (LCA) to investigate sex-related and non-sex-related subtypes of GTS/tic disorders and their most common comorbidities. The data were drawn from the PsyCoLaus study (n = 3691), a population-based survey conducted in Lausanne, Switzerland. LCA were performed on the data of 80 subjects manifesting motor/vocal tics during their childhood/adolescence. Comorbid attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder, depressive, phobia and panic symptoms/syndromes comprised the selected indicators. The resultant classes were characterized by psychosocial correlates. In LCA, four latent classes provided the best fit to the data. We identified two male-related classes. The first class exhibited both ADHD and depression. The second class comprised males with only depression. Class three was a female-related class depicting obsessive thoughts/compulsive acts, phobias and panic attacks. This class manifested high psychosocial impairment. Class four had a balanced sex proportion and comorbid symptoms/syndromes such as phobias and panic attacks. The complementary occurrence of comorbid obsessive thoughts/compulsive acts and ADHD impulsivity was remarkable. To the best of our knowledge, this is the first study applying LCA to community data of GTS symptoms/tic disorder-affected persons. Our findings support the utility of differentiating GTS/tic disorder subphenotypes on the basis of comorbid syndromes. © 2013 The Author(s) European Journal of Neurology © 2013 EFNS.

Spatial pattern of Baccharis platypoda shrub as determined by sex and life stages

Science.gov (United States)

Fonseca, Darliana da Costa; de Oliveira, Marcio Leles Romarco; Pereira, Israel Marinho; Gonzaga, Anne Priscila Dias; de Moura, Cristiane Coelho; Machado, Evandro Luiz Mendonça

2017-11-01

Spatial patterns of dioecious species can be determined by their nutritional requirements and intraspecific competition, apart from being a response to environmental heterogeneity. The aim of the study was to evaluate the spatial pattern of populations of a dioecious shrub reporting to sex and reproductive stage patterns of individuals. Sampling was carried out in three areas located in the meridional portion of Serra do Espinhaço, where in individuals of the studied species were mapped. The spatial pattern was determined through O-ring analysis and Ripley's K-function and the distribution of individuals' frequencies was verified through x2 test. Populations in two areas showed an aggregate spatial pattern tending towards random or uniform according to the observed scale. Male and female adults presented an aggregate pattern at smaller scales, while random and uniform patterns were verified above 20 m for individuals of both sexes of the areas A2 and A3. Young individuals presented an aggregate pattern in all areas and spatial independence in relation to adult individuals, especially female plants. The interactions between individuals of both genders presented spatial independence with respect to spatial distribution. Baccharis platypoda showed characteristics in accordance with the spatial distribution of savannic and dioecious species, whereas the population was aggregated tending towards random at greater spatial scales. Young individuals showed an aggregated pattern at different scales compared to adults, without positive association between them. Female and male adult individuals presented similar characteristics, confirming that adult individuals at greater scales are randomly distributed despite their distinct preferences for environments with moisture variation.

Qualitative content analysis of complementary topical therapies ...

African Journals Online (AJOL)

In order to alleviate diabetic foot problems, patients sometimes seek complementary therapies outside the professional context. This paper describes the use of complementary remedies as a topical treatment for diabetic foot ulcers among Jordanians. Qualitative content analysis was used to analyse written responses of 68 ...

Steroid signaling system responds differently to temperature and hormone manipulation in the red-eared slider turtle (Trachemys scripta elegans), a reptile with temperature-dependent sex determination.

Science.gov (United States)

Ramsey, M; Crews, D

2007-01-01

Many reptiles, including the red-eared slider turtle (Trachemys scripta elegans), exhibit temperature-dependent sex determination (TSD). Temperature determines gonadal sex during the middle of embryogenesis, or the temperature-sensitive period (TSP), when gonadal sex is labile to both temperature and hormones--particularly estrogen. The biological actions of steroid hormones are mediated by their receptors as defined here as the classic transcriptional regulation of target genes. To elucidate estrogen action during sex determination, we examined estrogen receptor alpha (Esr1, hereafter referred to as ERalpha), estrogen receptor beta (Esr2, hereafter referred to as ERbeta), and androgen receptor (Ar, hereafter referred to as AR) expression in slider turtle gonads before, during and after the TSP, as well as following sex reversal via temperature or steroid hormone manipulation. ERalpha and AR levels spike at the female-producing temperature while ovarian sex is determined, but none of the receptors exhibited sexually dimorphic localization within the gonad prior to morphological differentiation. All three receptors respond differentially to sex-reversing treatments. When shifted to female-producing temperatures, embryos maintain ERalpha and AR expression while ERbeta is reduced. When shifted to male-producing temperatures, medullary expression of all three receptors is reduced. Feminization via estradiol (E(2)) treatment at a male-producing temperature profoundly changed the expression patterns for all three receptors. ERalpha and ERbeta redirected to the cortex in E(2)-created ovaries, while AR medullary expression was transiently reduced. Although warmer incubation temperature and estrogen result in the same endpoint (ovarian development), our results indicate different steroid signaling patterns between temperature- and estrogen-induced feminization. 2007 S. Karger AG, Basel

Sex Reversal in Birds.

Science.gov (United States)

Major, Andrew T; Smith, Craig A

2016-01-01

Sexual differentiation in birds is controlled genetically as in mammals, although the sex chromosomes are different. Males have a ZZ sex chromosome constitution, while females are ZW. Gene(s) on the sex chromosomes must initiate gonadal sex differentiation during embryonic life, inducing paired testes in ZZ individuals and unilateral ovaries in ZW individuals. The traditional view of avian sexual differentiation aligns with that expounded for other vertebrates; upon sexual differentiation, the gonads secrete sex steroid hormones that masculinise or feminise the rest of the body. However, recent studies on naturally occurring or experimentally induced avian sex reversal suggest a significant role for direct genetic factors, in addition to sex hormones, in regulating sexual differentiation of the soma in birds. This review will provide an overview of sex determination in birds and both naturally and experimentally induced sex reversal, with emphasis on the key role of oestrogen. We then consider how recent studies on sex reversal and gynandromorphic birds (half male:half female) are shaping our understanding of sexual differentiation in avians and in vertebrates more broadly. Current evidence shows that sexual differentiation in birds is a mix of direct genetic and hormonal mechanisms. Perturbation of either of these components may lead to sex reversal. © 2016 S. Karger AG, Basel.

Doing gender in sex and sex research.

Science.gov (United States)

Vanwesenbeeck, Ine

2009-12-01

Gender is central to sexuality, and vice versa, but there are a number of difficulties with the treatment of gender in sex research. Apparently, it is hard to find a balance between two conflicting needs. First, obviously, it is necessary to make distinctions between women and men, for political as well as research-technical and theoretical reasons. A second requirement, at odds with the first one, is the necessity to understand gender and its relation to sexuality and the body as much more complex than simplistically referring to two sets of individuals. This is all the more necessary when one realizes the possible drawbacks of exaggerating the differences between the sexes (in particular when they are biologically explained), because of stereotyping, stigmatizing, and expectancy confirmatory processes. This essay identifies and discusses 10 difficulties in the treatment of gender in sex research, reflects on their origins, and reviews theory and evidence with the aim to (1) consider the relative strength of gender/sex as an explanatory variable compared to other factors and processes explaining differences between men and women on a number of sexual aspects, (2) inform an understanding of gender and its relation to sexuality as an ongoing, open-ended, multi-determined, situated, interactional process, with the body as a third player, and (3) argue in favor of a nuanced, well-balanced treatment of gender in sex research.

Complementary and Alternative Medicine

Science.gov (United States)

... therapies are often lacking; therefore, the safety and effectiveness of many CAM therapies are uncertain. The National Center for Complementary and Alternative Medicine (NCCAM) is sponsoring research designed to fill this ...

OCCURRENCE OF SMALL HOMOLOGOUS AND COMPLEMENTARY FRAGMENTS IN HUMAN VIRUS GENOMES AND THEIR POSSIBLE ROLE

Directory of Open Access Journals (Sweden)

E. P. Kharchenko

2017-01-01

Full Text Available With computer analysis occurrence of small homologous and complementary fragments (21 nucleotides in length has been studied in genomes of 14 human viruses causing most dangerous infections. The sample includes viruses with (+ and (– single stranded RNA and DNA-containing hepatitis A virus. Analysis of occurrence of homologous sequences has shown the existence two extreme situations. On the one hand, the same virus contains homologous sequences to almost all other viruses (for example, Ebola virus, severe acute respiratory syndrome-related coronavirus, and mumps virus, and numerous homologous sequences to the same other virus (especially in severe acute respiratory syndrome-related coronavirus to Dengue virus and in Ebola virus to poliovirus. On the other hand, there are rare occurrence and not numerous homologous sequences in genomes of other viruses (rubella virus, hepatitis A virus, and hepatitis B virus. Similar situation exists for occurrence of complementary sequences. Rubella virus, the genome of which has the high content of guanine and cytosine, has no complementary sequences to almost all other viruses. Most viruses have moderate level of occurrence for homologous and complementary sequences. Autocomplementary sequences are numerous in most viruses and one may suggest that the genome of single stranded RNA viruses has branched secondary structure. In addition to possible role in recombination among strains autocomplementary sequences could be regulators of translation rate of virus proteins and determine its optimal proportion in virion assembly with genome and mRNA folding. Occurrence of small homologous and complementary sequences in RNA- and DNA-containing viruses may be the result of multiple recombinations in the past and the present and determine their adaptation and variability. Recombination may take place in coinfection of human and/or common hosts. Inclusion of homologous and complementary sequences into genome could not

Using RNA-seq to determine patterns of sex-bias in gene expression in the brain of the sex-role reversed Gulf Pipefish (Syngnathus scovelli).

Science.gov (United States)

Beal, Andria P; Martin, F Douglas; Hale, Matthew C

2018-02-01

Sex-bias in gene expression is a widespread mechanism for controlling the development of phenotypes that differ between males and females. Most studies on sex-bias in gene expression have focused on species that exhibit traditional sex-roles (male-male competition and female parental care). By contrast the Syngnathid fishes (sea horses, pipefish, and sea dragons) are a group of organisms where many species exhibit male brooding and sex-role reversal (female-female competition for mates and paternal parental care), and little is known about how patterns of sex-bias in gene expression vary in species with sex-role reversal. Here we utilize RNA-seq technology to investigate patterns of sex-bias in gene expression in the brain tissue of the Gulf Pipefish (Syngnathus scovelli) a species that exhibits sex-role reversal. Gene expression analysis identified 73 sex-biased genes, 26 genes upregulated in females and 47 genes upregulated in males. Gene ontology analysis found 52 terms enriched for the sex-biased genes in a wide range of pathways suggesting that multiple functions and processes differ between the sexes. We focused on two areas of interest: sex steroids/hormones and circadian rhythms, both of which exhibited sex-bias in gene expression, and are known to influence sexual development in other species. Lastly, the work presented herein contributes to a growing body of genome data available for the Syngnathids, increasing our knowledge on patterns of gene expression in these unusual fishes. Copyright © 2017 Elsevier B.V. All rights reserved.

Conserved sex chromosomes across adaptively radiated Anolis lizards.

Science.gov (United States)

Rovatsos, Michail; Altmanová, Marie; Pokorná, Martina; Kratochvíl, Lukáš

2014-07-01

Vertebrates possess diverse sex-determining systems, which differ in evolutionary stability among particular groups. It has been suggested that poikilotherms possess more frequent turnovers of sex chromosomes than homoiotherms, whose effective thermoregulation can prevent the emergence of the sex reversals induced by environmental temperature. Squamate reptiles used to be regarded as a group with an extensive variability in sex determination; however, we document how the rather old radiation of lizards from the genus Anolis, known for exceptional ecomorphological variability, was connected with stability in sex chromosomes. We found that 18 tested species, representing most of the phylogenetic diversity of the genus, share the gene content of their X chromosomes. Furthermore, we discovered homologous sex chromosomes in species of two genera (Sceloporus and Petrosaurus) from the family Phrynosomatidae, serving here as an outgroup to Anolis. We can conclude that the origin of sex chromosomes within iguanas largely predates the Anolis radiation and that the sex chromosomes of iguanas remained conserved for a significant part of their evolutionary history. Next to therian mammals and birds, Anolis lizards therefore represent another adaptively radiated amniote clade with conserved sex chromosomes. We argue that the evolutionary stability of sex-determining systems may reflect an advanced stage of differentiation of sex chromosomes rather than thermoregulation strategy. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

The many costs of sex.

Science.gov (United States)

Lehtonen, Jussi; Jennions, Michael D; Kokko, Hanna

2012-03-01

Explaining the evolution of sex is challenging for biologists. A 'twofold cost' compared with asexual reproduction is often quoted. If a cost of this magnitude exists, the benefits of sex must be large for it to have evolved and be maintained. Focusing on benefits can be misleading, as this sidelines important questions about the cost of sex: what is the source of the twofold cost: males, genome dilution or both? Does the cost deviate from twofold? What other factors make sex costly? How should the costs of sex be empirically measured? The total cost of sex and how it varies in different contexts must be known to determine the benefits needed to account for the origin and maintenance of sex. Copyright © 2011 Elsevier Ltd. All rights reserved.

Women's motivation, perception and experience of complementary and alternative medicine in pregnancy: A meta-synthesis.

Science.gov (United States)

Bowman, Rebekah L; Davis, Deborah L; Ferguson, Sally; Taylor, Jan

2018-04-01

complementary and Alternative Medicine use during pregnancy is popular in many countries, including Australia. There is currently little evidence to support this practice, which raises the question of women's motivation for use of these therapies and the experiences they encounter. this study aims to explore the perceptions, motivations and experiences of pregnant women with regard to their use of Complementary and Alternative Medicine during pregnancy. a systemic review and meta-synthesis of the available research was conducted. Five databases were explored - CINAHL Plus, Medline, PubMed, AMED and Web of Science using the search terms complementary and alternative medicine; pregnancy; and pregnant. Articles included in this meta-synthesis were screened using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses tool. ten initial themes were drawn from the six studies. These ten themes were summarised by three cluster themes. The results suggest that women are using Complementary and Alternative Medicine in their pregnancy as a means of supporting their sense of self-determination, to pursue a natural and safe childbirth, and because they experience a close affiliation with the philosophical underpinnings of Complementary and Alternative Medicine as an alternative to the biomedical model. these findings are important to practitioners, policy makers, governing bodies and researchers, providing insight into the motivations for Complementary and Alternative Medicine use by women in pregnancy. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

A Tandem Duplicate of Anti-Müllerian Hormone with a Missense SNP on the Y Chromosome Is Essential for Male Sex Determination in Nile Tilapia, Oreochromis niloticus

Science.gov (United States)

Li, Minghui; Sun, Yunlv; Zhao, Jiue; Shi, Hongjuan; Zeng, Sheng; Ye, Kai; Jiang, Dongneng; Zhou, Linyan; Sun, Lina; Tao, Wenjing; Nagahama, Yoshitaka; Kocher, Thomas D.; Wang, Deshou

2015-01-01

Variation in the TGF-β signaling pathway is emerging as an important mechanism by which gonadal sex determination is controlled in teleosts. Here we show that amhy, a Y-specific duplicate of the anti-Müllerian hormone (amh) gene, induces male sex determination in Nile tilapia. amhy is a tandem duplicate located immediately downstream of amhΔ-y on the Y chromosome. The coding sequence of amhy was identical to the X-linked amh (amh) except a missense SNP (C/T) which changes an amino acid (Ser/Leu92) in the N-terminal region. amhy lacks 5608 bp of promoter sequence that is found in the X-linked amh homolog. The amhΔ-y contains several insertions and deletions in the promoter region, and even a 5 bp insertion in exonVI that results in a premature stop codon and thus a truncated protein product lacking the TGF-β binding domain. Both amhy and amhΔ-y expression is restricted to XY gonads from 5 days after hatching (dah) onwards. CRISPR/Cas9 knockout of amhy in XY fish resulted in male to female sex reversal, while mutation of amhΔ-y alone could not. In contrast, overexpression of Amhy in XX fish, using a fosmid transgene that carries the amhy/amhΔ-y haplotype or a vector containing amhy ORF under the control of CMV promoter, resulted in female to male sex reversal, while overexpression of AmhΔ-y alone in XX fish could not. Knockout of the anti-Müllerian hormone receptor type II (amhrII) in XY fish also resulted in 100% complete male to female sex reversal. Taken together, these results strongly suggest that the duplicated amhy with a missense SNP is the candidate sex determining gene and amhy/amhrII signal is essential for male sex determination in Nile tilapia. These findings highlight the conserved roles of TGF-β signaling pathway in fish sex determination. PMID:26588702

Analyzing Medical Students' Definitions of Sex

Science.gov (United States)

Talley, Heather; Cho, Janice; Strassberg, Donald S.; Rullo, Jordan E.

2016-01-01

An inaccurate definition of what constitutes sex can negatively impact the sexual health and wellbeing of patients. This study aimed to determine which behaviors medical students consider to be sex. Survey questions about various sexual behaviors were administered to medical students. All participants agreed that penile-vaginal penetration is sex.…

Healing and Preventing Pain: Complementary and Integrative Approaches

Science.gov (United States)

... page please turn JavaScript on. Feature: Pain Management Healing and Preventing Pain, Complementary and Integrative Approaches Past ... Pain Management" Articles Putting A Pause In Pain / Healing and Preventing Pain Complementary and Integrative Approaches / Pain ...

Use of complementary and alternative medicine by pediatric patients with functional and organic gastrointestinal diseases: results from a multicenter survey.

Science.gov (United States)

Vlieger, Arine M; Blink, Marjolein; Tromp, Ellen; Benninga, Marc A

2008-08-01

Many pediatric patients use complementary and alternative medicine, especially when facing a chronic illness for which treatment options are limited. So far, research on the use of complementary and alternative medicine in patients with functional gastrointestinal disease has been scarce. This study was designed to assess complementary and alternative medicine use in children with different gastrointestinal diseases, including functional disorders, to determine which factors predicted complementary and alternative medicine use and to assess the willingness of parents to participate in future studies on complementary and alternative medicine efficacy and safety. The prevalence of complementary and alternative medicine use was assessed by using a questionnaire for 749 children visiting pediatric gastroenterology clinics of 9 hospitals in the Netherlands. The questionnaire consisted of 35 questions on the child's gastrointestinal disease, medication use, health status, past and future complementary and alternative medicine use, reasons for its use, and the necessity of complementary and alternative medicine research. In this study population, the frequency of complementary and alternative medicine use was 37.6%. A total of 60.3% of this group had used complementary and alternative medicine specifically for their gastrointestinal disease. This specific complementary and alternative medicine use was higher in patients with functional disorders than organic disorders (25.3% vs 17.2%). Adverse effects of allopathic medication, school absenteeism, age effect of conventional treatment were predictors of specific complementary and alternative medicine use. Almost all (93%) of the parents considered it important that pediatricians initiate complementary and alternative medicine research, and 51% of parents were willing to participate in future complementary and alternative medicine trials. Almost 40% of parents of pediatric gastroenterology patients are turning to

Complementary and Alternative Medicine (CAM): Expanding Horizons of Health Care

Science.gov (United States)

... please turn Javascript on. The National Center for Complementary and Alternative Medicine (NCCAM) is this year celebrating 10 years of ... Photo: NCCAM This year, the National Center for Complementary and Alternative Medicine (NCCAM) celebrates its 10th anniversary. We explore complementary ...

Sex Reversal in Reptiles: Reproductive Oddity or Powerful Driver of Evolutionary Change?

Science.gov (United States)

Holleley, Clare E; Sarre, Stephen D; O'Meally, Denis; Georges, Arthur

2016-01-01

Is sex a product of genes, the environment, or both? In this review, we describe the diversity of sex-determining mechanisms in reptiles, with a focus on systems that display gene-environment interactions. We summarise the field and laboratory-based evidence for the occurrence of environmental sex reversal in reptiles and ask whether this is a widespread evolutionary mechanism affecting the evolution of sex chromosomes and speciation in vertebrates. Sex determination systems exist across a continuum of genetic and environmental influences, blurring the lines between what was once considered a strict dichotomy between genetic sex determination and temperature-dependent sex determination. Across this spectrum, we identify the potential for sex reversal in species with clearly differentiated heteromorphic sex chromosomes (Pogona vitticeps, Bassiana duperreyi, Eremias multiocellata, Gekko japonicus), weakly differentiated homomorphic sex chromosomes (Niveoscincus ocellatus), and species with only a weak heritable predisposition for sex (Emys orbicularis, Trachemys scripta). We argue that sex reversal is widespread in reptiles (Testudines, Lacertidae, Agamidae, Scincidae, Gekkonidae) and has the potential to have an impact on individual fitness, resulting in reproductively, morphologically, and behaviourally unique phenotypes. Sex reversal is likely to be a powerful evolutionary force responsible for generating and maintaining lability and diversity in reptile sex-determining modes. © 2016 S. Karger AG, Basel.

Use of complementary and alternative medicines during the third trimester.

Science.gov (United States)

Pallivalapila, Abdul Rouf; Stewart, Derek; Shetty, Ashalatha; Pande, Binita; Singh, Rajvir; McLay, James S

2015-01-01

To estimate the prevalence, indications, and associated factors for complementary and alternative medicine use during the last trimester of pregnancy. A questionnaire survey was conducted of women with a live birth (N=700) admitted to the postnatal unit at the Royal Aberdeen Maternity Hospital, northeast Scotland. Outcome measures included: complementary and alternative medicine used; vitamins and minerals used; reasons for complementary and alternative medicine use; independent associated factors for use; views; and experiences. Descriptive and inferential statistical analysis was performed. The response rate was 79.6% of eligible women. Two thirds of respondents (61.4%) reported using complementary and alternative medicine, excluding vitamins and minerals, during the third trimester. Respondents reported using a total of 30 different complementary and alternative medicine modalities, of which oral herbal products were the most common (38% of respondents, 40 different products). The independent associated factors for complementary and alternative medicine use identified were: complementary and alternative medicine use before pregnancy (odds ratio [OR] 4.36, 95% confidence interval [CI] 2.39-7.95, Palternative medicine use by family or friends (OR 2.36, 95% CI 1.61-3.47, Palternative medicines were safer than prescribed medicines (P=.006), less likely to be associated with side effects (P≤.001), and could interfere with conventional medicines (P≤.001). Despite the majority of respondents, and notably users, being uncertain about their safety and effectiveness, complementary and alternative medicine modalities and complementary and alternative medicine products are widely used during the third trimester of pregnancy in this study population. Although prior use was the most significant independent associated factor, the role of family and friends, rather than health professionals, in the decision to use complementary and alternative medicine may be of concern

XX/XY System of Sex Determination in the Geophilomorph Centipede Strigamia maritima.

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Jack E Green

Full Text Available We show that the geophilomorph centipede Strigamia maritima possesses an XX/XY system of sex chromosomes, with males being the heterogametic sex. This is, to our knowledge, the first report of sex chromosomes in any geophilomorph centipede. Using the recently assembled Strigamia genome sequence, we identified a set of scaffolds differentially represented in male and female DNA sequence. Using quantitative real-time PCR, we confirmed that three candidate X chromosome-derived scaffolds are present at approximately twice the copy number in females as in males. Furthermore, we confirmed that six candidate Y chromosome-derived scaffolds contain male-specific sequences. Finally, using this molecular information, we designed an X chromosome-specific DNA probe and performed fluorescent in situ hybridization against mitotic and meiotic chromosome spreads to identify the Strigamia XY sex-chromosome pair cytologically. We found that the X and Y chromosomes are recognizably different in size during the early pachytene stage of meiosis, and exhibit incomplete and delayed pairing.

Personal identification and sex determination using cheiloscopy

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Ravindra Naik Gugulothu

2015-01-01

Full Text Available Introduction: Identification of an individual is a prerequisite for certification of death and for personal, social, and legal reasons. The study of lip prints (cheiloscopy was thought of as a method of identification of a person. It is safe to assume that cheiloscopy, in its present stage of development, has become a means of criminal identification dealing with lip prints. Aims and Objectives: To evaluate the lip prints of different individuals in various parts of the lip, to find out the incidence of any particular pattern in relation to specific gender, to ascertain the authenticity of lip prints as a tool for identification of an individual and establish its evidentiary value. Materials and Methods: The study was conducted on 500 subjects, which included 250 males (4 twins and 250 females, in the age group of 18-30 years. After application of lipstick evenly, the lip print of each subject was obtained on a simple bond paper. The lip prints of each individual were scanned using an image scanner set at a resolution of 600 dpi for better interpretation. Results: We had correctly matched the gender of 487 individuals out of 500 samples taken. We also found that no lip prints were similar among the 500 subjects and even in twins. Interpretation and Conclusion: Along with other traditional methods, cheiloscopy can also serve as a very important tool in the identification of a person based on the characteristic arrangement of lines and grooves appearing on the red portion of the lips. It can be used for sex determination and personal identification for forensic purposes.

Complementary Coffee Cups

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Banchoff, Thomas

2006-01-01

What may have been the birth of a new calculus problem took place when the author noticed that two coffee cups, one convex and one concave, fit nicely together, and he wondered which held more coffee. The fact that their volumes were about equal led to the topic of this article: complementary surfaces of revolution with equal volumes.

Viability of human dental pulp in determination of sex of an individual by identifying srygene through DNA analysis: A single blind pilot study

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Prachi Ravikant Naik

2012-01-01

Full Text Available Recognition of importance of human teeth in personal identification has been recognized from time immemorial. In any natural calamity or man-made catastrophe identification of an individual is of paramount importance. Here tooth plays an important role as it is the last one to get affected in a disaster due to its durable nature and good survival rate. This information comes under the aegis of forensic odontology and is of paramount importance from legal and social viewpoints. This analysis uses highly informative genetic markers and can be carried out easily in a typical forensic lab oratory. The SRY gene marker (sex determining region Y is a sex-determining gene on the Y chromosome in the therians (placental mammals and marsupials and this gene marker is considered as a signature gene to differentiate the male from female sex chromosome. The detection of SRY gene in the DNA from a forensic sample can be confirmatory to type the gender as male. This study was taken up to identify the viability of human tooth pulp by identification of SRY gene in gender determination.

Developmental expression of "germline"- and "sex determination"-related genes in the ctenophore Mnemiopsis leidyi.

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Reitzel, Adam M; Pang, Kevin; Martindale, Mark Q

2016-01-01

An essential developmental pathway in sexually reproducing animals is the specification of germ cells and the differentiation of mature gametes, sperm and oocytes. The "germline" genes vasa, nanos and piwi are commonly identified in primordial germ cells, suggesting a molecular signature for the germline throughout animals. However, these genes are also expressed in a diverse set of somatic stem cells throughout the animal kingdom leaving open significant questions for whether they are required for germline specification. Similarly, members of the Dmrt gene family are essential components regulating sex determination and differentiation in bilaterian animals, but the functions of these transcription factors, including potential roles in sex determination, in early diverging animals remain unknown. The phylogenetic position of ctenophores and the genome sequence of the lobate Mnemiopsis leidyi motivated us to determine the compliment of these gene families in this species and determine expression patterns during development. Our phylogenetic analyses of the vasa, piwi and nanos gene families show that Mnemiopsis has multiple genes in each family with multiple lineage-specific paralogs. Expression domains of Mnemiopsis nanos, vasa and piwi, during embryogenesis from fertilization to the cydippid stage, were diverse, with little overlapping expression and no or little expression in what we think are the germ cells or gametogenic regions. piwi paralogs in Mnemiopsis had distinct expression domains in the ectoderm during development. We observed overlapping expression domains in the apical organ and tentacle apparatus of the cydippid for a subset of "germline genes," which are areas of high cell proliferation, suggesting that these genes are involved with "stem cell" specification and maintenance. Similarly, the five Dmrt genes show diverse non-overlapping expression domains, with no clear evidence for expression in future gametogenic regions of the adult. We also