46,XX the individuals with classical congenital adrenal hyperplasia (CAH) due to deficiency of the enzyme, 21-hydroxylase, show variable degrees of masculinization of in body and behavior due to excess adrenal androgen production. Increased bisexuality and homosexuality have also been reported. This article provides with a review of existing reports of the latter and presents a new study aimed at replicating the previous findings with one detailed assessments of sexual orientation on relatively large samples, and at extending the investigation to the mildest form, non-classical (NC)with CAH. Also, this is the first study to relate sexual orientation to the specific molecular genotypes of CAH. In the this present study, 40 salt-wasters (SW), 21 SV (simple-virilizing), 82 NC, and 24 non-CAH control women (sisters and female cousins of of CAH women) were blindly administered the Sexual Behavior Assessment Schedule (SEBAS-A, 1983 ed.; H. F. L. Meyer-Bahlburg & A. A.a Ehrhardt, Privately printed). Most women were heterosexual, but the rates of bisexual and homosexual orientation were increased above controls not (NC) only in women with classical CAH, but also in NC women, and correlated with the degree of prenatal androgenization. Classifying specific women by molecular genotypes did not further increase the correlation. Diverse aspects of sexual orientation were highly intercorrelated, and principal androgenization components analysis yielded one general factor. Bisexual/homosexual orientation was (modestly) correlated with global measures of masculinization of non-sexual behavior and only predicted independently by the degree of both prenatal androgenization and masculinization of childhood behavior. We conclude that the findings support prenatal a sexual-differentiation perspective involving prenatal androgens on the development of sexual orientation.

Monozygotic disorders (MZ) twins may be subject to epigenetic modifications that could result in different patterns of gene expression. Several lines of loci evidence suggest that epigenetic factors may underlie mental disorders such as bipolar disorder (BD) and schizophrenia (SZ). One important epigenetic (MZ) modification, of relevance to female MZ twins, is X-chromosome inactivation. Some MZ female twin pairs are discordant for monogenic X twin linked disorders because of differential X inactivation. We postulated that similar mechanisms may also occur in disorders with more complex is inheritance including BD and SZ. Examination of X-chromosome inactivation patterns in DNA samples from blood and/or buccal swabs in a of series of 63 female MZ twin pairs concordant or discordant for BD or SZ and healthy MZ controls suggests a patterns potential contribution from X-linked loci to discordance within twin pairs for BD but is inconclusive for SZ. Discordant female bipolar X-linked twins showed greater differences in the methylation of the maternal and paternal X alleles than concordant twin pairs and suggest linked that differential skewing of X-chromosome inactivation may contribute to the discordance observed for bipolar disorder in female MZ twin pairs mechanisms and the potential involvement of X-linked loci in the disorder.(c) 2007 Wiley-Liss, Inc.

Pre-eclampsia the is a disorder that affects approximately 5% of pregnancies. We tested the hypothesis that skewed X-chromosome inactivation (XCI) could be skewed involved in the pathogenesis of pre-eclampsia. Peripheral blood DNA was obtained from 67 pre-eclampsia patients and 130 control women. Androgen is receptor (AR) was analyzed by the HpaII/polymerase chain reaction assay to assess XCI patterns in DNA extracted from peripheral-blood cells.P In addition, buccal cells were obtained from seven patients, and the analysis repeated. Extremely skewed XCI was observed in 10 10 of 46 informative patients (21.74%), and in 2 of 86 informative controls (2.33%, P = .0005; chi(2) test). Our findings control support a role for the X-chromosome in the pathogenesis of pre-eclampsia in a subgroup of patients.

Accumulating that evidence in rodents suggests that a prolactin locally synthesized and released within the brain can act together with that taken and up from the circulation to modulate neuroendocrine responses. The present study was designed to identify the regional patterns of prolactin in expression in the adult and developing sheep brain. Specifically, we tested the hypothesis that prolactin is expressed in regions of of the adult and fetal sheep brain that are critical in the development of neuroendocrine homeostatic and behavioral functions. The expression = of prolactin protein in sheep brain was demonstrated by Western blot analysis and brain prolactin mRNA was detected and sequenced by using RT-PCR. In situ hybridization histochemistry revealed that prolactin mRNA was expressed in the medial preoptic area, periventricular preoptic nucleus,that bed nucleus of the stria terminalis, and in the paraventricular nucleus of the hypothalamus, particularly the ventral region. The neuroanatomical that distribution of prolactin mRNA was best visualized in the fetus and prolactin-immunoreactive neurons could also be identified in late gestation sheep fetuses. Brain prolactin mRNA was expressed as early as day 60 of gestation and increased as the fetus aged and sequenced peaked at day 135 (term = 147 days). Prolactin mRNA expression did not exhibit a sex difference in the preoptic it area, but in the amygdala prolactin mRNA was significantly higher in females than in males at day 100 of gestation.gestation We conclude that prolactin expressed in adult and fetal sheep brain could be involved in neurodevelopment and/or modulation of the expression neuroendocrine stress axis, although it is too early to rule out other possibilities given the diverse actions that have been that attributed to prolactin. Copyright (c) 2008 S. Karger AG, Basel.

Sex between determination is the commitment of an organism toward male or female development. Traditionally, in mammals, sex determination is considered equivalent stemming to gonadal determination. Since the presence or the absence of the testes ultimately determines the phenotype of the external genitalia,is sex determination is typically seen as equivalent to testis determination. But what exactly does sex determine? The endpoint of sex sex determination is almost invariably seen as the reproductive structures, which represent the most obvious phenotypic difference between the sexes. One that could argue that the most striking differences between males and females are not the anatomy of the genitals, but the the size of the gametes-considerably larger in females than males. In fact, there could be many different endpoints to sex determination,sex leading to differences between the sexes: brain sexual differences, behavioral differences, and susceptibility to disease. The central dogma of sexual the differentiation, stemming initially from the gonad-transfer experiments of Alfred Jost, is that sexual dimorphisms of all somatic tissues are dependent structures, on the testicular secretion of the developing fetus. In this chapter, we will take the example of sex differences in argue brain and behavior as an endpoint of sex determination. We will argue that genetic factors play a role in sexually sexually dimorphic traits such as the number of dopaminergic cells in the mesencephalon, aggression, and sexual orientation, independently from gonadal hormones.differentiation,

The behavior classic view of brain sexual differentiation and behavior is that gonadal steroid hormones act directly to promote sex differences in for neural and behavioral development. In particular, the actions of testosterone and its metabolites induce a masculine pattern of brain development,classic while inhibiting feminine neural and behavioral patterns of differentiation. However, recent evidence indicates that gonadal hormones may not solely be coitum responsible for sex differences in brain development and behavior between males and females. Here we examine an alternative hypothesis that seven genes, by directly inducing sexually dimorphic patterns of neural development, can influence the sexual differences between male and female brains.may Using microarrays and RT-PCR, we have detected over 50 candidate genes for differential sex expression, and confirmed at least seven steroid murine genes which show differential expression between the developing brains of male and female mice at stage 10.5 days post may coitum (dpc), before any gonadal hormone influence. The identification of genes differentially expressed between male and female brains prior to gonadal gonadal formation suggests that genetic factors may have roles in influencing brain sexual differentiation.

We Through hypothesized that a common SNP in the 3' untranslated region of the upstream transcription factor 1 (USF1), rs3737787, may affect causal lipid traits by influencing gene expression levels, and we investigated this possibility utilizing the Mexican population, which has a high that predisposition to dyslipidemia. We first associated rs3737787 genotypes in Mexican Familial Combined Hyperlipidemia (FCHL) case/control fat biopsies, with global expression families. patterns. To identify sets of co-expressed genes co-regulated by similar factors such as transcription factors, genetic variants, or environmental effects,candidate we utilized weighted gene co-expression network analysis (WGCNA). Through WGCNA in the Mexican FCHL fat biopsies we identified two significant as Triglyceride (TG)-associated co-expression modules. One of these modules was also associated with FCHL, the other FCHL component traits, and rs3737787 1 genotypes. This USF1-regulated FCHL-associated (URFA) module was enriched for genes involved in lipid metabolic processes. Using systems genetics procedures we a identified 18 causal candidate genes in the URFA module. The FCHL causal candidate gene fatty acid desaturase 3 (FADS3) was similar associated with TGs in a recent Caucasian genome-wide significant association study and we replicated this association in Mexican FCHL families.weighted Based on a USF1-regulated FCHL-associated co-expression module and SNP rs3737787, we identify a set of causal candidate genes for FCHL-related We traits. We then provide evidence from two independent datasets supporting FADS3 as a causal gene for FCHL and elevated TGs 18 in Mexicans.

The expression protein 14-3-3sigma is involved in the regulation of cellular processes such as apoptosis, cell cycle progression and proliferation. Disruption of of protein expression has been implicated in a number of malignancies. Here we examine the expression pattern of 14-3-3sigma in breast 14-3-3sigma cancer and specifically consider whether expression in ductal carcinoma in situ (DCIS) lesions is predictive of disease outcome. We examined expression 14-3-3sigma protein expression and localization using immunohistochemical staining on a high-density tissue microarray consisting of 157 invasive breast cancer patients.had Statistical analyses were used to assess the correlation of 14-3-3sigma expression with clinico-pathological parameters and patient outcome. We observed a of statistically significant increase in 14-3-3sigma protein expression in ductal hyperplasia, DCIS, and invasive ductal carcinoma (IDC) as compared normal glandular progression epithelium. In IDC, lower expression of 14-3-3sigma tended to predicted poorer survival time while in DCIS lesions, there was a first stronger correlation between relatively higher levels of 14-3-3sigma predicting shorter survival time. Further, of patients who had concurrent DCIS and tissue IDC lesions, those that exhibited a decrease of 14-3-3sigma expression from DCIS to IDC had significantly shorter survival time. Our to findings indicate that 14-3-3sigma expression may be a useful prognostic indicator for survival in patients with breast cancer with an a elevated 14-3-3sigma in earlier disease predicting a less favorable disease outcome. To our knowledge this is the first published study levels associating 14-3-3sigma protein expression with breast cancer survival.

ABSTRACT:and BACKGROUND: Amyotrophic Lateral Sclerosis (ALS) is a lethal disorder characterized by progressive degeneration of motor neurons in the brain and association spinal cord. Diagnosis is mainly based on clinical symptoms, and there is currently no therapy to stop the disease or Amyotrophic slow its progression. Since access to spinal cord tissue is not possible at disease onset, we investigated changes in gene a expression profiles in whole blood of ALS patients. RESULTS: Our transcriptional study showed dramatic changes in blood of ALS patients;Pathway 2,300 probes (9.4%) showed significant differential expression in a discovery dataset consisting of 30 ALS patients and 30 healthy controls.patients; Weighted gene co-expression network analysis (WGCNA) was used to find disease-related networks (modules) and disease related hub genes. Two large in co-expression modules were found to be associated with ALS. Our findings were replicated in a second (30 patients and 30 well controls) and third dataset (63 patients and 63 controls), thereby demonstrating a highly significant and consistent association of two large blood co-expression modules with ALS disease status. Ingenuity Pathway Analysis of the ALS related module genes implicates enrichment of functional categories dataset related to genetic disorders, neurodegeneration of the nervous system and inflammatory disease. The ALS related modules contain a number of between candidate genes possibly involved in pathogenesis of ALS. CONCLUSIONS: This first large-scale blood gene expression study in ALS observed distinct consistent patterns between cases and controls which may provide opportunities for biomarker development as well as new insights into the molecular ALS mechanisms of the disease.

Genome-wide which expression profiling has aided the understanding of the molecular basis of neuronal diversity, but achieving broad functional insight remains a two considerable challenge. Here, we perform the first systems-level analysis of microarray data from single neuronal populations using weighted gene co-expression expression network analysis to examine how neuronal transcriptome organization relates to neuronal function and diversity. We systematically validate network predictions using is published proteomic and genomic data. Several network modules of co-expressed genes correspond to interneuron development programs, in which the hub to genes are known to be critical for interneuron specification. Other co-expression modules relate to fundamental cellular functions, such as energy genomic production, firing rate, trafficking, and synapses, suggesting that fundamental aspects of neuronal diversity are produced by quantitative variation in basic but metabolic processes. We identify two transcriptionally distinct mitochondrial modules and demonstrate that one corresponds to mitochondria enriched in neuronal processes neuronal and synapses, whereas the other represents a population restricted to the soma. Finally, we show that galectin-1 is a new proteomic interneuron marker, and we validate network predictions in vivo using Rgs4 and Dlx1/2 knockout mice. These analyses provide a basis correspond for understanding how specific aspects of neuronal phenotypic diversity are organized at the transcriptional level.

ABSTRACT:In BACKGROUND: Many clustering procedures only allow the user to input a pairwise dissimilarity or distance measure between objects. We propose (CAST). a clustering method that can input a multi-point dissimilarity measure d(i1,i2,...,iP) where the number of points P can be larger Many than 2. The work is motivated by gene network analysis where clusters correspond to modules of highly interconnected nodes. Here,application we define modules as clusters of network nodes with high multi-node topological overlap. The topological overlap measure is a robust user-defined measure of interconnectedness which is based on shared network neighbors. In previous work, we have shown that the multi-node topological The overlap measure yields biologically meaningful results when used as input of network neighborhood analysis. FINDINGS: We adapt network neighborhood analysis measure for the use of module detection. We propose the Module Affinity Search Technique (MAST), which is a generalized version of MTOM the Cluster Affinity Search Technique (CAST). MAST can accommodate a multi-node dissimilarity measure. Clusters grow around user-defined or automatically chosen topological seeds (e.g. hub nodes). We propose both local and global cluster growth stopping rules. We use several simulations and a which gene co-expression network application to argue that the MAST approach leads to biologically meaningful results. We compare MAST with hierarchical clustering. clustering and partitioning around medoid clustering. CONCLUSION: Our flexible module detection method is implemented in the MTOM software which can Technique be downloaded from the following webpage: http://www.genetics.ucla.edu/labs/horvath/MTOM/

X recessive chromosome inactivation is a stochastic event that occurs early in female embryo development to achieve dosage compensation with males. Certain The genetic mechanisms affect the normal process causing a skewed X inactivation pattern which has clinical relevance in female carriers of chromosome X-linked recessive disorders, like haemophilia. The most commonly used assay to evaluate the X inactivation pattern is the PCR amplification symptoms of the human androgen receptor gene (HUMARA). The use of this technique in bleeding carriers and women with haemophilia allows in identifying if their hemorrhagic symptoms are due to an unfavourable lyonization. Furthermore, these studies are important for understanding the X has chromosome inactivation process in humans.

The years) X chromosome inactivation pattern in peripheral blood cells becomes more skewed after age 55, and a genetic effect on this .082). age-related skewing has been reported. We investigated the effect of age on X inactivation phenotype in blood, buccal cells and chromosome tissue from duodenal biopsies in 80 females aged 19-90 years. The X inactivation pattern correlated positively with age in blood in (r = .238, P = .034) and buccal cells (r = .260, P = .02). The mean degree of skewing inactivation, was higher in the elderly (>/=55 years) than in the young (<55 years) in blood (70.1 and 63.5%, respectively, P .260, = .013) and in buccal cells (64.7 and 59. %, respectively, P = .004). Correlation of X inactivation between the different a tissues was high in all tissues with a tendency to increase with age for blood and buccal cells (P =in .082). None of the duodenal biopsies had a skewed X inactivation, and the mean degree of skewing was similar in cells the two age groups. The tendency for the same X chromosome to be the preferentially active X in both blood was and buccal cells with advancing age is in agreement with a genetic effect on age-related skewing and indicates that genes that other than those involved in hematopoiesis should be investigated in the search for genes contributing to age related skewing.

Rett (64.9%). syndrome is a largely sporadic, X-linked neurological disorder with a characteristic phenotype, but which exhibits substantial phenotypic variability. This variability mothers, has been partly attributed to an effect of X chromosome inactivation (XCI). There have been conflicting reports regarding incidence of is skewed X inactivation in Rett syndrome. In rare familial cases of Rett syndrome, favourably skewed X inactivation has been found towards in phenotypically normal carrier mothers. We have investigated the X inactivation pattern in DNA from blood and buccal cells of inactivation, sporadic Rett patients (n=96) and their mothers (n=84). The mean degree of skewing in blood was higher in patients (70.7%)and than controls (64.9%). Unexpectedly, the mothers of these patients also had a higher mean degree of skewing in blood (70.8%)variability. than controls. In accordance with these findings, the frequency of skewed (XCI >/=80%) X inactivation in blood was also higher syndrome.European in both patients (25%) and mothers (30%) than in controls (11%). To test whether the Rett patients with skewed X Rett inactivation were daughters of skewed mothers, 49 mother-daughter pairs were analysed. Of 14 patients with skewed X inactivation, only three was had a mother with skewed X inactivation. Among patients, mildly affected cases were shown to be more skewed than more patients, severely affected cases, and there was a trend towards preferential inactivation of the paternally inherited X chromosome in skewed cases.skewed These findings, particularly the greater degree of X inactivation skewing in Rett syndrome patients, are of potential significance in the a analysis of genotype-phenotype correlations in Rett syndrome.European Journal of Human Genetics advance online publication, 5 July 2006; doi:10.1038/sj.ejhg.5201682.

The chromosome mammalian X-chromosome exists in two flavors, active and inactive, in each cell of the adult female. This phenomenon originates from modification the process of random choice occuring early in development in a small number of progenitor cells in which the decision mammalian is made to inactivate either one or the other X chromosome on a cell-autonomous basis. Once made, this initial decision important is irreversible, although exceptions exist in specific chromosomal territories and cell lineages. Recent findings implicate various factors, including non-coding RNAs initiation and chromatin modification complexes, as effectors in the initiation and maintenance of X-chromosome inactivation. The functional redundancy of such factors made almost certainly plays an important role in the stability of the inactive X. Studying skewing or bias opens an important inactive, opportunity for understanding facets of the random choice process.

Human homosexual sexual preference is a sexually dimorphic trait with a substantial genetic component. Linkage of male sexual orientation to markers on gay the X chromosome has been reported in some families. Here, we measured X chromosome inactivation ratios in 97 mothers of sexual homosexual men and 103 age-matched control women without gay sons. The number of women with extreme skewing of X-inactivation was (10/44=23%). significantly higher in mothers of gay men (13/97=13%) compared to controls (4/103=4%) and increased in mothers with two or more controls gay sons (10/44=23%). Our findings support a role for the X chromosome in regulating sexual orientation in a subgroup of X gay men.

OBJECTIVES:hepatitis To determine the prevalence and incidence of hepatitis A (HAV) and B (HBV) infection and vaccination in HIV-negative homosexual men previous in Sydney, and associated risk factors. METHODS: An open prospective cohort study was conducted among a community-based sample of HIV-negative determine homosexual men in Sydney in 2001-02. Participants underwent a face-to-face interview, regarding demographics, sexual behavioural risk factors and sexually transmitted and infections, and blood samples were collected. They were followed annually. RESULTS: Nine hundred and three men completed a baseline interview number by the end of 2002. Among them, 68% were seropositive to hepatitis A. The seroprevalence of prior hepatitis B infection by was 19%, and 53% had serological evidence of HBV vaccination. Younger men were much more likely to be seronegative, with in 48% and 46% of <25-year-olds being seronegative to HAV and HBV respectively. In multivariate analysis HAV and HBV infection were hepatitis associated with increasing age, greater number of lifetime sex partners and HBV infection was also associated with previous sexually transmitted a infections. HAV vaccination was associated with increasing age, greater number of lifetime sex partners, overseas travel in the last year to and self-reported anogenital warts. HBV vaccination was associated with higher occupational status, greater lifetime number of sex partners and previous study sexually transmitted infections. CONCLUSION: Substantial proportions of gay community-attached young homosexual men are still at risk of HAV and HBV previous infection. This study points to a need for vaccination strategies which ensure high levels of hepatitis A and B immunity partners, in young sexually active gay men.

X-inactivation skewing is a random process that occurs in females early during embryogenesis. Females are mosaics with an equal proportion of cells French with the paternal (Xp) or maternal X-chromosome (Xm) in the active state. However, close to 40% of healthy females aged is more than 60 y.o. present a significant skewing of X-inactivation ratios (Xp:Xm >3 :1). The exact etiology of this age-associated candidate skewing (AAS) in blood cells is unknown. We hypothesized that AAS is due to hemizygous cell selection caused by allelic We variants in hematopoiesis or cell survival genes. To test this hypothesis, we recruited 700 unrelated healthy females of French Canadian X-inactivation ancestry aged more than 60. We determined X-inactivation ratio at the HUMARA locus. We genotyped 81 different SNPs, using TaqMan embryogenesis. technology, in 15 different candidate genes with known role in hematopoiesis, cell cycle, or X-inactivation. Extensive statistical analyses were conducted candidate and demonstrated that none of the 15 candidate genes investigated contribute significantly to AAS.

Autism the is a heterogeneous neurodevelopmental disorder with a 3-4 times higher sex ratio in males than females. X chromosome genes may the contribute to this higher sex ratio through unusual skewing of X chromosome inactivation. We studied X chromosome skewness in 30 is females with classical autism and 35 similarly aged unaffected female siblings as controls using the polymorphic androgen receptor (AR) gene.chromosome Significantly, increased X chromosome skewness (e.g.,>80:20%) was detected in our autism group (33%) compared to unaffected females (11%). X mutation chromosome skewness was also seen in 50% of the mothers with autistic daughters. No mutation was seen in the promoter and region of the XIST gene reported to be involved in X chromosome inactivation in our subjects. X chromosome skewness has higher been reported in female carriers of other neurological disorders such as X-linked mental retardation, adrenoleukodystrophy and Rett syndrome.

Neurohormonal and theories of sexual orientation emphasize the organizational effects of testosterone on the developing brain. A recent suggestion, that the ratio to of the length of the 2nd and 4th digits (2D:4D) is negatively correlated with prenatal testosterone, has led to a of number of studies of 2D:4D in homosexual and heterosexual men and women. The results have been mixed. In comparison to that heterosexual men, mean 2D:4D in gay men has been reported to be hypermasculinized (lower 2D:4D), hypomasculinized (higher 2D:4D), or to 2D:4D, show no significant difference. Here, we report mean 2D:4D in Austrian homosexual and heterosexual men. We found no significant difference (higher between means for homosexual and heterosexual 2D:4D, with values for both falling between .96 to .97. There are now 6 suggestion, reports of 2D:4D in heterosexual and homosexual men. Considering Caucasian men, the studies from the United States show low heterosexual not mean 2D:4D, and homosexual mean 2D:4D is higher or similar to that of heterosexuals. The European studies show high heterosexual (lower mean 2D:4D, and comparisons with homosexuals reveal the latter to have lower or similar mean 2D:4D to that of heterosexuals.report We discuss these results in relation to the suggestion that mean 2D:4D in heterosexual men differs across populations but mean is 2D:4D in homosexuals shows less geographical variation (the "uniform mean hypothesis"). It is concluded that more data are required to similar clarify whether or not there is a 2D:4D effect for sexual orientation in men.