scholarly journals Gender Disparities in Bladder Cancer

2021 ◽  
Author(s):  
Yingsheng Zhang ◽  
Dan Theodorescu ◽  
Xue Li
Keyword(s):  
Bladder Cancer ◽  
Sex Hormones ◽  
Sex Chromosomes ◽  
Sex Chromosome ◽  
Gender Disparities ◽  
Sexually Dimorphic ◽  
Biological Sex ◽  
Gonad Differentiation ◽  
Develop Bladder Cancer

Biological sex is an independent risk factor of cancer. Men are three to five times more likely than women to develop bladder cancer even when known risk factors are taken into consideration. Development of sex in mammals is often viewed as a two-step process. The first step is sex determination, of which the XX and XY sex chromosome complements trigger gonad differentiation to form the ovary and testis, respectively. After that, sex hormones secreted by gonads initiate sexually dimorphic differentiation of nongonadal tissues. However, this model has been challenged by recent findings revealing an independent contribution of sex chromosomes to sexual dimorphism. In this chapter, we discuss how the sex chromosomes and sex hormones together cause gender disparities in bladder cancer. We propose a concept of epigenetic sex – epigenetic differences between males and females – and suggest that the sex epigenome is a previously unknown biasing factor contributing to gender disparities in bladder cancer.

scholarly journals Sexually dimorphic recombination can facilitate the establishment of sexually antagonistic polymorphisms in guppies

2018 ◽  
Author(s):  
Roberta Bergero ◽  
Jim Gardner ◽  
Beth Bader ◽  
Lengxob Yong ◽  
Deborah Charlesworth
Keyword(s):  
Sex Chromosomes ◽  
Poecilia Reticulata ◽  
Common Ancestor ◽  
Sex Chromosome ◽  
Empirical Support ◽  
Male Meiosis ◽  
Sexually Dimorphic ◽  
Sex Linkage ◽  
Recombination Suppression ◽  
Males And Females

Summary/AbstractRecombination suppression between sex chromosomes is often stated to evolve in response to polymorphisms for mutations that affect fitness of males and females in opposite directions (sexually antagonistic, or SA, mutations), but direct empirical support is lacking. The sex chromosomes of the fish Poecilia reticulata (the guppy) carry SA polymorphisms, making them excellent for testing this hypothesis for the evolution of sex linkage. We resequenced genomes of male and female guppies and, unexpectedly, found that variants on the sex chromosome indicate no extensive region with fully sex-linked genotypes, though many variants show strong evidence for partial sex linkage. We present genetic mapping results that help understand the evolution of the guppy sex chromosome pair. We find very different distributions of crossing over in the two sexes, with recombination events in male meiosis detected only at the tips of the chromosomes. The guppy may exemplify a route for sex chromosome evolution in which low recombination in males, likely evolved in a common ancestor, has facilitated the establishment of sexually antagonistic polymorphisms.

scholarly journals Identification of sex chromosomes using genomic and cytogenetic methods in a range-expanding spider, Argiope bruennichi (Araneae: Araneidae)

2021 ◽  
Author(s):  
Monica M Sheffer ◽  
Mathilde M Cordellier ◽  
Martin Forman ◽  
Malte Grewoldt ◽  
Katharina Hoffmann ◽  
...  
Keyword(s):  
X Chromosome ◽  
Sex Chromosomes ◽  
Sex Chromosome ◽  
Chromosome Complement ◽  
Gc Content ◽  
Sexually Dimorphic ◽  
Behavioral Experiments ◽  
X Chromosomes ◽  
Male Karyotype ◽  
And Behavior

Differences between sexes in growth, ecology and behavior strongly shape species biology. In some animal groups, such as spiders, it is difficult or impossible to identify the sex of juveniles. This information would be useful for field surveys, behavioral experiments, and ecological studies on e.g. sex ratios and dispersal. In species with sex chromosomes, sex can be determined based on the specific sex chromosome complement. Additionally, information on the sequence of sex chromosomes provides the basis for studying sex chromosome evolution. We combined cytogenetic and genomic data to identify the sex chromosomes in the sexually dimorphic spider Argiope bruennichi, and designed RT-qPCR sex markers. We found that genome size and GC content of this spider falls into the range reported for the majority of araneids. The male karyotype is formed by 24 acrocentric chromosomes with an X1X20 sex chromosome system, with little similarity between X chromosomes, suggesting origin of these chromosomes by X chromosome fission or early duplication of an X chromosome and subsequent independent differentiation of the copies. Our data suggest similarly sized X chromosomes in A. bruennichi. They are smaller chromosomes of the complement. Our findings open the door to new directions in spider evolutionary and ecological research.

scholarly journals Sleep Deprivation alters the influence of biological sex on active-phase sleep behavior

2020 ◽  
Author(s):  
India Nichols ◽  
Scott Vincent ◽  
September Hesse ◽  
J. Christopher Ehlen ◽  
Allison Brager ◽  
...  
Keyword(s):  
Sex Differences ◽  
Sex Chromosomes ◽  
Sex Chromosome ◽  
Chromosome Complement ◽  
Active Phase ◽  
Sleep Loss ◽  
Model Systems ◽  
Poor Sleep ◽  
Biological Sex ◽  
Sleep Amount

AbstractPoor sleep is a hazard of daily life that oftentimes cannot be avoided. Gender differences in daily sleep and wake patterns are widely reported; however, it remains unclear how biological sex, which is comprised of genetic and endocrine components, directly influences sleep regulatory processes. In the majority of model systems studied thus far, sex differences in daily sleep amount are predominant during the active (wake) phase of the sleep-wake cycle. The pervasiveness of sex differences in sleep amount throughout phylogeny suggests a strong underlying genetic component. The goal of the current study is to determine if sex differences in active-phase sleep amount are dependent on sex chromosomes in mice.Sleep was examined in the four-core genotype (FCG) mouse model, whose sex chromosome complement (XY, XX) is independent of sex phenotype (male or female). In this line, sex phenotype is determined by the presence or absence of the Sry gene, which is dissociated from the Y chromosome. Polysomnographic sleep recordings were obtained from gonadectomized (GDX) FCG mice to examine spontaneous sleep states and the ability to recover from sleep loss. We report that during the active-phase, the presence of the Sry gene accounts for most sex differences during spontaneous sleep; however, during recovery from sleep loss, sex differences in sleep amount are partially driven by sex chromosome complement. These results suggest that genetic factors on the sex chromosomes encode the homeostatic response to sleep loss.

scholarly journals Sex chromosome contributions to sex differences in multiple sclerosis susceptibility and progression

2018 ◽  
Vol 24 (1) ◽  
pp. 22-31 ◽  
Author(s):  
Rhonda R Voskuhl ◽  
Amr H Sawalha ◽  
Yuichiro Itoh
Keyword(s):  
Multiple Sclerosis ◽  
Sex Differences ◽  
Sex Hormones ◽  
X Chromosome ◽  
Sex Chromosomes ◽  
Sex Chromosome ◽  
Autoimmune Encephalomyelitis ◽  
Chromosome Gene ◽  
The Central Nervous System ◽  
Bone Marrow Chimeras

Background: Why are women more susceptible to multiple sclerosis, but men have worse disability progression? Sex differences in disease may be due to sex hormones, sex chromosomes, or both. Objective: Determine whether differences in sex chromosomes can contribute to sex differences in multiple sclerosis using experimental autoimmune encephalomyelitis. Methods: Sex chromosome transgenic mice, which permit the study of sex chromosomes not confounded by differences in sex hormones, were used to examine an effect of sex chromosomes on autoimmunity and neurodegeneration, focusing on X chromosome genes. Results: T-lymphocyte DNA methylation studies of the X chromosome gene Foxp3 suggested that maternal versus paternal imprinting of X chromosome genes may underlie sex differences in autoimmunity. Bone marrow chimeras with the same immune system but different sex chromosomes in the central nervous system suggested that differential expression of the X chromosome gene Toll-like receptor 7 in neurons may contribute to sex differences in neurodegeneration. Conclusion: Mapping the transcriptome and methylome in T lymphocytes and neurons in females versus males could reveal mechanisms underlying sex differences in autoimmunity and neurodegeneration.

Do the Hominid-Specific Regions of X–Y Homology Contain Candidate Genes Potentially Involved in a Critical Event Linked to Speciation?

2004 ◽  
Author(s):  
Carole A. Sargent ◽  
Patricia Blanco ◽  
Nabeel A. Affara
Keyword(s):  
Cognitive Function ◽  
Candidate Genes ◽  
X Chromosome ◽  
Sex Chromosomes ◽  
Sex Chromosome ◽  
Great Apes ◽  
Critical Event ◽  
Functional Genes ◽  
Sexually Dimorphic ◽  
Critical Events

It has been postulated that the critical events leading to major differences between humans and the great apes are associated with major changes on sex chromosomes. Regions of homology between the human sex chromosomes have arisen at different points during mammalian evolution. The two largest blocks are specific to hominids, having appeared at some time after the divergence of humans and chimpanzees. These are the second pairing region found at the telomeres of the sex chromosome long arms and a region of homology between Xq21.3 (X chromosome long arm) and Yp11 (Y chromosome short arm). Questions arise as to whether these regions of the sex chromosomes contain functional genes and these genes might be candidates for the differences in cognitive function that distinguish modern humans from their ancestors. Furthermore, divergence between functional sequences on the X and the Y may lead to a more subtle sexually dimorphic variation.

Monotreme sex chromosomes - implications for the evolution of amniote sex chromosomes

2009 ◽  
Vol 21 (8) ◽  
pp. 943 ◽  
Author(s):  
Paul D. Waters ◽  
Jennifer A. Marshall Graves
Keyword(s):  
Sex Determination ◽  
Sex Chromosomes ◽  
Sex Chromosome ◽  
Female Development ◽  
Comparative Gene Mapping ◽  
Y Chromosomes ◽  
Daunting Task ◽  
Platypus Genome ◽  
Genetic Events

In vertebrates, a highly conserved pathway of genetic events controls male and female development, to the extent that many genes involved in human sex determination are also involved in fish sex determination. Surprisingly, the master switch to this pathway, which intuitively could be considered the most critical step, is inconsistent between vertebrate taxa. Interspersed in the vertebrate tree there are species that determine sex by environmental cues such as the temperature at which eggs are incubated, and then there are genetic sex-determination systems, with male heterogametic species (XY systems) and female heterogametic species (ZW systems), some of which have heteromorphic, and others homomorphic, sex chromosomes. This plasticity of sex-determining switches in vertebrates has made tracking the events of sex chromosome evolution in amniotes a daunting task, but comparative gene mapping is beginning to reveal some striking similarities across even distant taxa. In particular, the recent completion of the platypus genome sequence has completely changed our understanding of when the therian mammal X and Y chromosomes first arose (they are up to 150 million years younger than previously thought) and has also revealed the unexpected insight that sex determination of the amniote ancestor might have been controlled by a bird-like ZW system.

scholarly journals Sex determination of human remains from peptides in tooth enamel

2017 ◽  
Vol 114 (52) ◽  
pp. 13649-13654 ◽  
Author(s):  
Nicolas Andre Stewart ◽  
Raquel Fernanda Gerlach ◽  
Rebecca L. Gowland ◽  
Kurt J. Gron ◽  
Janet Montgomery
Keyword(s):  
Sex Determination ◽  
Dna Analysis ◽  
Sex Chromosome ◽  
Tooth Enamel ◽  
Human Remains ◽  
Routine Activity ◽  
Biological Sex ◽  
Os Coxae ◽  
First Time

The assignment of biological sex to archaeological human skeletons is a fundamental requirement for the reconstruction of the human past. It is conventionally and routinely performed on adults using metric analysis and morphological traits arising from postpubertal sexual dimorphism. A maximum accuracy of ∼95% is possible if both the cranium and os coxae are present and intact, but this is seldom achievable for all skeletons. Furthermore, for infants and juveniles, there are no reliable morphological methods for sex determination without resorting to DNA analysis, which requires good DNA survival and is time-consuming. Consequently, sex determination of juvenile remains is rarely undertaken, and a dependable and expedient method that can correctly assign biological sex to human remains of any age is highly desirable. Here we present a method for sex determination of human remains by means of a minimally destructive surface acid etching of tooth enamel and subsequent identification of sex chromosome-linked isoforms of amelogenin, an enamel-forming protein, by nanoflow liquid chromatography mass spectrometry. Tooth enamel is the hardest tissue in the human body and survives burial exceptionally well, even when the rest of the skeleton or DNA in the organic fraction has decayed. Our method can reliably determine the biological sex of humans of any age using a body tissue that is difficult to cross-contaminate and is most likely to survive. The application of this method will make sex determination of adults and, for the first time, juveniles a reliable and routine activity in future bioarcheological and medico-legal science contexts.

scholarly journals Mechanisms for sex differences in energy homeostasis

2019 ◽  
Vol 62 (2) ◽  
pp. R129-R143 ◽  
Author(s):  
Chunmei Wang ◽  
Yong Xu
Keyword(s):  
Sex Differences ◽  
Energy Balance ◽  
Sex Hormones ◽  
Sex Chromosomes ◽  
Energy Homeostasis ◽  
Liver Fat ◽  
Sexually Dimorphic ◽  
Multiple Organs ◽  
Specific Regulation ◽  
Underlying Mechanisms

Sex differences exist in the regulation of energy homeostasis. Better understanding of the underlying mechanisms for sexual dimorphism in energy balance may facilitate development of gender-specific therapies for human diseases, e.g. obesity. Multiple organs, including the brain, liver, fat and muscle, play important roles in the regulations of feeding behavior, energy expenditure and physical activity, which therefore contribute to the maintenance of energy balance. It has been increasingly appreciated that this multi-organ system is under different regulations in male vs female animals. Much of effort has been focused on roles of sex hormones (including androgens, estrogens and progesterone) and sex chromosomes in this sex-specific regulation of energy balance. Emerging evidence also indicates that other factors (not sex hormones/receptors and not encoded by the sex chromosomes) exist to regulate energy homeostasis differentially in males vs females. In this review, we summarize factors and signals that have been shown to regulate energy homeostasis in a sexually dimorphic fashion and propose a framework where these factors and signals may be integrated to mediate sex differences in energy homeostasis.

scholarly journals Differential Gene Expression between Fungal Mating Types Is Associated with Sequence Degeneration

2020 ◽  
Vol 12 (4) ◽  
pp. 243-258 ◽  
Author(s):  
Wen-Juan Ma ◽  
Fantin Carpentier ◽  
Tatiana Giraud ◽  
Michael E Hood
Keyword(s):  
Differential Expression ◽  
Differentially Expressed Genes ◽  
Mating Type ◽  
Sex Chromosomes ◽  
Sex Chromosome ◽  
Gc Content ◽  
Differentially Expressed ◽  
Mating Types ◽  
Sexual Antagonism ◽  
Recombination Suppression

Abstract Degenerative mutations in non-recombining regions, such as in sex chromosomes, may lead to differential expression between alleles if mutations occur stochastically in one or the other allele. Reduced allelic expression due to degeneration has indeed been suggested to occur in various sex-chromosome systems. However, whether an association occurs between specific signatures of degeneration and differential expression between alleles has not been extensively tested, and sexual antagonism can also cause differential expression on sex chromosomes. The anther-smut fungus Microbotryum lychnidis-dioicae is ideal for testing associations between specific degenerative signatures and differential expression because 1) there are multiple evolutionary strata on the mating-type chromosomes, reflecting successive recombination suppression linked to mating-type loci; 2) separate haploid cultures of opposite mating types help identify differential expression between alleles; and 3) there is no sexual antagonism as a confounding factor accounting for differential expression. We found that differentially expressed genes were enriched in the four oldest evolutionary strata compared with other genomic compartments, and that, within compartments, several signatures of sequence degeneration were greater for differentially expressed than non-differentially expressed genes. Two particular degenerative signatures were significantly associated with lower expression levels within differentially expressed allele pairs: upstream insertion of transposable elements and mutations truncating the protein length. Other degenerative mutations associated with differential expression included nonsynonymous substitutions and altered intron or GC content. The association between differential expression and allele degeneration is relevant for a broad range of taxa where mating compatibility or sex is determined by genes located in large regions where recombination is suppressed.

Evolution of Sex Chromosome Heteromorphy in Geographic Populations of the Japanese Tago’s Brown Frog Complex

2021 ◽  
pp. 1-9
Author(s):  
Chiao Kuwana ◽  
Hiroyuki Fujita ◽  
Masataka Tagami ◽  
Takanori Matsuo ◽  
Ikuo Miura
Keyword(s):  
Sex Chromosomes ◽  
Sex Chromosome ◽  
Mitochondrial Gene ◽  
Population Level ◽  
Chromosome 7 ◽  
Geographic Population ◽  
Geographic Populations ◽  
Western Japan ◽  
Brown Frog ◽  
Eastern Japan

The sex chromosomes of most anuran amphibians are characterized by homomorphy in both sexes, and evolution to heteromorphy rarely occurs at the species or geographic population level. Here, we report sex chromosome heteromorphy in geographic populations of the Japanese Tago’s brown frog complex (2n = 26), comprising Rana sakuraii and R. tagoi. The sex chromosomes of R. sakuraii from the populations in western Japan were homomorphic in both sexes, whereas chromosome 7 from the populations in eastern Japan were heteromorphic in males. Chromosome 7 of R. tagoi, which is distributed close to R. sakuraii in eastern Japan, was highly similar in morphology to the Y chromosome of R. sakuraii. Based on this and on mitochondrial gene sequence analysis, we hypothesize that in the R. sakuraii populations from eastern Japan the XY heteromorphic sex chromosome system was established by the introduction of chromosome 7 from R. tagoi via interspecies hybridization. In contrast, chromosome 13 of R. tagoi from the 2 large islands in western Japan, Shikoku and Kyushu, showed a heteromorphic pattern of constitutive heterochromatin distribution in males, while this pattern was homomorphic in females. Our study reveals that sex chromosome heteromorphy evolved independently at the geographic lineage level in this species complex.

Sign in / Sign up

Export Citation Format

Share Document