Genetic Sex Research Articles

The Rattlesnake W Chromosome: A GC-Rich Retroelement Refugium with Retained Gene Function Across Ancient Evolutionary Strata.

Sex chromosomes diverge after the establishment of recombination suppression, resulting in differential sex-linkage of genes involved in genetic sex determination and dimorphic traits. This process produces systems of male or female heterogamety wherein the Y and W chromosomes are only present in one sex and are often highly degenerated. Sex-limited Y and W chromosomes contain valuable information about the evolutionary transition from autosomes to sex chromosomes, yet detailed characterizations of the structure, composition, and gene content of sex-limited chromosomes are lacking for many species. In this study, we characterize the female-specific W chromosome of the prairie rattlesnake (Crotalus viridis) and evaluate how recombination suppression and other processes have shaped sex chromosome evolution in ZW snakes. Our analyses indicate that the rattlesnake W chromosome is over 80% repetitive and that an abundance of GC-rich mdg4 elements has driven an overall high degree of GC-richness despite a lack of recombination. The W chromosome is also highly enriched for repeat sequences derived from endogenous retroviruses and likely acts as a “refugium” for these and other retroelements. We annotated 219 putatively functional W-linked genes across at least two evolutionary strata identified based on estimates of sequence divergence between Z and W gametologs. The youngest of these strata is relatively gene-rich, however gene expression across strata suggests retained gene function amidst a greater degree of degeneration following ancient recombination suppression. Functional annotation of W-linked genes indicates a specialization of the W chromosome for reproductive and developmental function since recombination suppression from the Z chromosome.

Omics approaches to discover pathophysiological pathways contributing to human pain.

Omics approaches to discover pathophysiological pathways contributing to human pain.

Karyotypic Analysis of Children with Disorders of Sex Development (DSD) at Children Hospital & ICH, Lahore

Aim: To determine the frequency of different karyotypes in children with DSD presented at The Children Hospital & ICH, Lahore Study design: Cross sectional analytical Place and Duration of Study: Department of Genetics, Children Hospital and ICH, Lahore, from Jan 2016 to June 2017. Methodology: The study was conducted on 83 adolescent children with any form of DSD after taking an informed consent. A detailed history was taken and sex of rearing was noted. Physical examination was done to know the morphological sex while karyotyping of all the cases was done for the confirmation of their genetic sex. All the findings were recorded on a predesigned proforma. The cases that have undergone any surgical correction procedure for genital ambiguity were excluded. Data was analyzed by SPSS 21. Results: Out of 83 cases, 27(32.5%) cases were reared as male at birth while 56(67.4%) were reared as female. Karyotypic analysis was done in all 83 cases. 27 cases who were reared as male, their karyotypic analysis of male sex of rearing showed a chromosomal compliment of 46XY in 25(92.5%), 46XX in 01(3.7%), 46XXY in 01(3.7%). Out of 56 cases of female sex of rearing, 45(80.3%) had 46XX karyotype 03(5.3%) had 46XY karyotype, 45X0 in 07(12.5%) and one case (1.7%) showed a XXX karyotype. Conclusion: To ensure the high-quality life for such an individual, there is an urgent need for correct sex assignment. Chromosomal analysis is important as a first step in determining an accurate genetic sex before the costly diagnostic tests and surgical procedure. Keywords: Intersex, Ambiguous genitalia, Karyotyping

Corazonin Neurons Contribute to Dimorphic Ethanol Sedation Sensitivity in Drosophila melanogaster.

Exposure to alcohol has multiple effects on nervous system function, and organisms have evolved mechanisms to optimally respond to the presence of ethanol. Sex differences in ethanol-induced behaviors have been observed in several organisms, ranging from humans to invertebrates. However, the molecular mechanisms underlying the dimorphic regulation of ethanol-induced behaviors remain incompletely understood. Here, we observed sex differences in ethanol sedation sensitivity in Drosophila Genome Reference Panel (DGRP) lines of Drosophila melanogaster compared to the absence of dimorphism in standard laboratory wildtype and control lines. However, in dose response experiments, we were able to unmask dimorphic responses for the control mutant line w1118 by lowering the testing ethanol concentration. Notably, feminization of the small population of Corazonin (Crz) neurons in males was sufficient to induce female-like sedation sensitivity. We also tested the role of the transcription factor apontic (apt) based on its known expression in Crz neurons and its regulation of sedation responses. Interestingly, loss of function apt mutations increased sedation times in both males and females as compared to controls. No significant difference between male and female apt mutants was observed, suggesting a possible role of apt in the regulation of dimorphic ethanol-induced responses. Thus, our results shed light into the mechanisms regulating sex-differences in ethanol-induced behaviors at the cellular and molecular level, suggesting that the genetic sex in a small neuronal population plays an important role in modulating sex differences in behavioral responses to ethanol.

Sex-specific association between coffee consumption and incident chronic kidney disease: a population-based analysis of 359,906 participants from the UK Biobank.

Background:The risk for chronic kidney disease (CKD) is influenced by genetic predisposition, sex, and lifestyle. Previous research indicates that coffee is a potentially protective factor in CKD. The current study aims to investigate whether sex disparity exists in the coffee–CKD association, and whether genetic risk of CKD or genetic polymorphisms of caffeine metabolism affect this association.Methods:A total of 359,906 participants from the UK Biobank who were enrolled between 2006 and 2010 were included in this prospective cohort study, which aimed to estimate the hazard ratios for coffee intake and incident CKD using a Cox proportional hazard model. Allele scores of CKD and caffeine metabolism were additionally adjusted for in a subsample with qualified genetic data (n = 255,343). Analyses stratified by genetic predisposition, comorbidities, and sex hormones were performed. Tests based on Bayesian model averaging were conducted to ascertain the robustness of the results.Results:Coffee was inversely associated with CKD in a dose-dependent manner. The effects of coffee did not differ across different strata of genetic risk for CKD, but were more evident among slower genetically predicted caffeine metabolizers. Significant sex disparity was observed (P value for interaction = 0.013), in that coffee drinking was only associated with the risk reduction of CKD in females. Subgroup analysis revealed that testosterone and sex hormone-binding globulin (SHBG), but not estradiol, modified the coffee–CKD association.Conclusions:In addition to the overall inverse coffee–CKD association that was observed in the general population, we could also establish that a sex disparity existed, in that females were more likely to experience the benefit of the association. Testosterone and SHBG may partly account for the sex disparity.

Abstract 1532: Short RNAs v2.0: isomiRs, tRFs, and rRFs represent numerous novel opportunities for developing potent, precision-medicine-aware diagnostics, prognostics, and therapeutics

Abstract Background: It has been twenty-eight years since the first microRNA (miRNA) was reported in the worm C. elegans. Since then, researchers have discovered miRNAs in animals, plants, and viruses. They also showed that miRNAs are critical regulators of many cellular processes in homeostasis and disease. The advent of deep sequencing helped discover many novel miRNAs, pinpointed miRNAs that are dysregulated in cancers and other diseases, and established that miRNAs have isoforms (isomiRs). Deep sequencing also proved instrumental in discovering two more populous classes of short RNAs, the tRNA-derived fragments (tRFs) and the rRNA-derived fragments (rRFs). In the last decade, others and we generated strong evidence that isomiRs, tRFs, and rRFs regulate messenger RNA (mRNA) and protein abundance, directly and indirectly. Methods: IsomiRs, tRFs, and rRFs arise from precursors whose genomic distribution is non-random. Many of these precursors contain sequence segments that resemble one another's or are present in unrelated genomic sequences. These factors obfuscate the molecules’ identity and genomic origin, muddle their biogenesis details, and complicate the design of experiments. Thus, to help study isomiRs, tRFs, and rRFs we had to develop specialized tools that tackle these complications. We analyzed tens of thousands of human samples using these tools, including specimens of primary human tissues, cancer cell lines, and biofluids. Results: We were the first to show that the expression of isomiRs, tRFs, and rRFs is regimented and depends on tissue type and disease. We were also first to show that their expression additionally depends on genetic ancestry, sex, and age. Our findings highlight the involvement of isomiRs, tRFs, and rRFs in previously unsuspected regulatory interactions. These interactions are currently uncharacterized and depend on cell context and, unexpectedly, on personal attributes. These dependencies are consequential. Indeed, we showed for many cancers that specific isomiRs, tRFs, and rRFs predispose patients of a given sex or ancestry to aggressive cancer biology. Conclusions: Our pan-cancer analyses show that isomiRs, tRFs, and rRFs offer unparalleled granularity when studying normal physiology, cancer, and the molecular biology of health disparities. Improving our understanding of the molecules’ dependence on tissue, disease, and personal attributes (e.g., sex, ancestry, age) will help develop better diagnostics, prognostics, and new approaches to personalized therapies. Preliminary reports provide strong evidence in this regard. Because very little is known currently about these three classes of short RNAs, data-driven approaches will be essential to all these efforts. Citation Format: Isidore Rigoutsos. Short RNAs v2.0: isomiRs, tRFs, and rRFs represent numerous novel opportunities for developing potent, precision-medicine-aware diagnostics, prognostics, and therapeutics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1532.

Biotechnological manipulation of the transition from genetic to temperature-dependent sex determination to obtain high quality neomale in aquaculture

Sex control is an essential technology to produce mono-sex populations with high growth rates and product quality in aquaculture. To produce an all-female population in fish with the XX/XY sex determination system, the generation of XX neomales is the critical step and they have been successfully created by different approaches, such as androgens, aromatase inhibitors and high temperature treatment. However, there is no comprehensive comparison of testis structure, quality of sperm and offspring in XX neomales produced by different approaches. Yellow catfish are an excellent model to study sex determination and sex reversal since robust sex-specific molecular markers and genetic sex determination have been identified. Previously, we observed that 17α-methyltestosterone (MT) treatment could not induce functional testes in XX yellow catfish. In this study, we found that high-temperature treatment caused a delay in ovarian development instead of sex reversal in yellow catfish. However, high temperature combined with aromatase inhibitor (Letrozole, LZ) treatment could dramatically improve the efficiency of sex reversal compared with using LZ alone (the neomale was designated XXm-LZ), while they showed the same testis phenotype. Interestingly, the offspring of XXm-LZ transitioned from genetic to temperature-dependent sex determination, which could be easily sex reversed after treatment with high temperature (the neomale was designated XXm-HT-1). Then, we evaluated the reproductive performances and sperm parameters in XY male, XXm-LZ and XXm-HT-1 neomales. Strikingly, the fertilization rate, hatching rate and survival rate of XXm-HT-1 catfish were as good as those of XYm yellow catfish and better than those of XXm-LZ yellow catfish, while the malformation rate of fries produced by XXm-HT-1 catfish was significantly lower than that of XXm-LZ catfish. In addition, the expression of miR-141/−200a/−429b and dmrt1/pfpdz1 was negatively and positively correlated with sperm quality, respectively. However, the transition from genetic to temperature-dependent sex determination was transient and cannot be completely inherited by the next generation in yellow catfish. We concluded that precise application of the transition from genetic to temperature-dependent sex determination could produce the highest quality neomales for sex control in aquaculture after comparing different approaches.

Sex Differences in Acute Neuroendocrine Responses to Stressors in Rodents and Humans.

Sex differences in the neuroendocrine response to acute stress occur in both animals and humans. In rodents, stressors such as restraint and novelty induce a greater activation of the hypothalamic-pituitary-adrenal axis (HPA) in females compared to males. The nature of this difference arises from steroid actions during development (organizational effects) and adulthood (activational effects). Androgens decrease HPA stress responsivity to acute stress, while estradiol increases it. Androgenic down-regulation of HPA responsiveness is mediated by the binding of testosterone (T) and dihydrotestosterone (DHT) to the androgen receptor, as well as the binding of the DHT metabolite, 3β-diol, to the β form of the estrogen receptor (ERβ). Estradiol binding to the α form of the estrogen receptor (ERα) increases HPA responsivity. Studies of human sex differences are relatively few and generally employ a psychosocial paradigm to measure stress-related HPA activation. Men consistently show greater HPA reactivity than women when being evaluated for achievement. Some studies have found greater reactivity in women when being evaluated for social performance. The pattern is inconsistent with rodent studies but may involve the differential nature of the stressors employed. Psychosocial stress is nonphysical and invokes a significant degree of top-down processing that is not easily comparable to the types of stressors employed in rodents. Gender identity may also be a factor based on recent work showing that it influences the neural processing of positive and negative emotional stimuli independent of genetic sex. Comparing different types of stressors and how they interact with gender identity and genetic sex will provide a better understanding of sex steroid influences on stress-related HPA reactivity.

Mapping sex-determination region and screening DNA markers for genetic sex identification in largemouth bass (Micropterus salmoides)

Largemouth bass (Micropterus salmoides) has become an important species of freshwater aquaculture in China, due to its characteristics of strong adaptability, fast growth, and good meat quality. The external morphological differences between the two sexes are not obvious, so it is impossible to accurately discriminate and identify the biological sex of largemouth bass with traditional methods. It is necessary to develop sex-specific molecular markers for research and industry purposes. In this study, 688 largemouth bass were re-sequenced, and a 260-Kb sex-linked region was identified combining genome-wide association analysis and Fst analysis. In this region, 158 sexually dimorphic SNPs and 37 sexually dimorphic insertions/deletions (InDels) were obtained. Three InDels larger than 10 bp were selected and proved to be accurate for discriminating the sex of largemouth bass. The three sex-specific markers developed and identified in this study further confirmed that largemouth bass belonged to the XX♀-XY♂ system, and provided a useful tool for elucidating the molecular mechanism of sex determination and promoting sex-controlled breeding.

Correction to: Genetic sex test for the short-beaked echidna (Tachyglossus aculeatus)

Correction to: Genetic sex test for the short-beaked echidna (Tachyglossus aculeatus)

Genetic background and sex control the outcome of high-fat diet feeding in mice

SummaryThe sharp increase in obesity prevalence worldwide is mainly attributable to changes in physical activity and eating behavior but the metabolic and clinical impacts of these obesogenic conditions vary between sexes and genetic backgrounds. This warrants personalized treatments of obesity and its complications, which require a thorough understanding of the diversity of metabolic responses to high-fat diet intake. By analyzing nine genetically diverse mouse strains, we show that much like humans, mice exhibit a huge variety of physiological and biochemical responses to high-fat diet. The strains exhibit various degrees of alterations in their phenotypic makeup. At the transcriptome level, we observe dysregulations of immunity, translation machinery, and mitochondrial genes. At the biochemical level, the enzymatic activity of mitochondrial complexes is affected. The diversity across mouse strains, diets, and sexes parallels that found in humans and supports the use of diverse mouse populations in future mechanistic or preclinical studies on metabolic dysfunctions.

Effect of breed and some non-genetic factors on growth performance of sheep under temperate conditions of Kashmir

The data pertaining to 4849 birth records spanning over a period of 21 years (1997–2017) of different genetic groups were collected from Mountain Research Centre for sheep and goat Station (MRCSG), Shere Kashmir University of Agricultural Science and Technology, Kashmir (SKUAST-K), Shuhama, Kashmir to investigate the effects of genetic group and non-genetic factors on growth performance of Bakarwal, Corriedale, Hampshire x Corrriedale Cross, Hampshire, Non-descript x Corriedale Cross, Non-descript x Polled Dorset Cross, Polled Dorset x Corriedale, Polled Dorset and South down sheep genetic groups. The non-genetic factors considered were period of birth sex of lamb whereas the growth profile traits considered were birth weight (BW), weaning weight (W3), six months body weight (W6), yearling body weight (W12), average daily gain from birth to weaning (ADG1), metabolic mass at weaning (W30.75), Kleiber ratio from birth to weaning (KR1), average daily gain from weaning to yearling age (ADG2), metabolic mass at yearling age (W120.75) and Kleiber ratio from weaning to yearling age (KR2). The overall least-squares means for BW, W3, W6, W12, ADG1, W30.75, KR1, ADG2, W120.75 and KR2 were 3.47 ± 0.04 kg, 13.30 ± 0.15 kg, 18.13 ± 0.19 kg, 23.79 ± 0.25 kg, 107.58 ± 1.54 g/day, 6.93 ± 0.06 kg, 15.20 ± 0.12, 37.21 ± 0.86, 10.81 ± 0.09 and 3.37 ± 0.06, respectively. The effect of genetic group and period was highly significant (p < 0.01) on all the traits under study whereas effect of sex was significant (p < 0.05) on BW, W3, W6, W12, ADG-1, ADG-2, W30.75 and W120.75 with sexual dimorphism of 1.03, 1.08, 1.09, 1.06, 1.03, 1.05, 1.07, 1.09, 1.05 and 1.04 for BW, W3, ADG1, W30.75, KR1, W6, W12, ADG2, W120.75 and KR2, respectively. The effect of interaction of genetic group and period of birth was highly significant (p > 0.01) whereas the effect of interaction of sex and period of birth was significant (p > 0.05) on all the traits under study. The effect of interaction of genetic group and sex was significant on BW, W3, ADG1 and W30.75 only. Pre-weaning average daily gains (ADG1) and Kleiber ratio (KR1) were higher than post-weaning average daily gains (ADG2) and Kleiber ratio (KR2), respectively in all genetic groups. Whereas the metabolic mass at weaning (W30.75) was lower than metabolic mass at yearling age (W120.75) in all genetic groups. The non-genetic factors of sex and period were observed to be important sources variation in the growth performance of sheep. The study concludes that Hampshire x Corrriedale cross outperformed other genetic groups with respect to ADG2 and W12. Further, environment plays significant role in performance of genotype. Hence, Hampshire x Corrriedale cross should intersemated to produce and evaluate F2 generation for post-weaning growth rate.

Evaluation of Knowledge, Attitudes, and Practices Related to Osteoporosis and Correlates of Perceived High Risk among People Living in Two Main Districts of Lebanon.

Background The prevalence of osteoporosis is increasing in Lebanon. Aim We evaluated the knowledge, attitudes, and practices related to osteoporosis and correlates of its perceived high risk among people living in Beirut and Mount Lebanon districts of Lebanon. Methods This study is a cross-sectional study which consisted of 376 participants that were selected from the two districts within two or three households after two geographical areas were randomly selected from each stratum classified by education and altitude. They were then asked to fill a KAP survey on osteoporosis and provide information on factors likely related to its perceived high risk. Results The majority of participants had a low (20.2%) and moderate (65.4%) knowledge of osteoporosis, with a higher knowledge in females than in males. A higher percentage of young people perceived it as a serious health risk than that of older people. In contrast, 85.9% participants reported drinking caffeinated beverages and 51.6% participants reported that they do not exercise. Glucose intolerance due to epigenetic and genetic factors, female sex, and older age were risk factors of a perceived high risk of osteoporosis, while any physical exercise, abstention from caffeine for 48 to 72 hours, and higher education were protective factors. Conclusion A nationwide KAP study should be conducted; likewise, awareness campaigns should be adopted.

Differential Regulation of Mouse Hippocampal Gene Expression Sex Differences by Chromosomal Content and Gonadal Sex.

Common neurological disorders, like Alzheimer’s disease (AD), multiple sclerosis (MS), and autism, display profound sex differences in prevalence and clinical presentation. However, sex differences in the brain with health and disease are often overlooked in experimental models. Sex effects originate, directly or indirectly, from hormonal or sex chromosomal mechanisms. To delineate the contributions of genetic sex (XX v. XY) versus gonadal sex (ovaries v. testes) to the epigenomic regulation of hippocampal sex differences, we used the Four Core Genotypes (FCG) mouse model which uncouples chromosomal and gonadal sex. Transcriptomic and epigenomic analyses of ~ 12-month-old FCG mouse hippocampus, revealed genomic context-specific regulatory effects of genotypic and gonadal sex on X- and autosome-encoded gene expression and DNA modification patterns. X-chromosomal epigenomic patterns, classically associated with X-inactivation, were established almost entirely by genotypic sex, independent of gonadal sex. Differences in X-chromosome methylation were primarily localized to gene regulatory regions including promoters, CpG islands, CTCF binding sites, and active/poised chromatin, with an inverse relationship between methylation and gene expression. Autosomal gene expression demonstrated regulation by both genotypic and gonadal sex, particularly in immune processes. These data demonstrate an important regulatory role of sex chromosomes, independent of gonadal sex, on sex-biased hippocampal transcriptomic and epigenomic profiles. Future studies will need to further interrogate specific CNS cell types, identify the mechanisms by which sex chromosomes regulate autosomes, and differentiate organizational from activational hormonal effects.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12035-022-02860-0.

Sex locus and sex markers identification using whole genome pool-sequencing approach in the largemouth bass (Micropterus Salmoides L.)

The mechanism of sex determination in teleost evolves in an amazing speed contrary to mammals and birds. Different populations of the same species may use different sex determination systems. Largemouth bass is an aquaculture importance and recreational fish, which belongs to the family of Centrarchidae, genus Micropterus. However, molecular basis of genetic sex determination currently remains unclear. We applied a whole genome pool-sequencing approach to better characterize sex determination in this fish. Our results confirmed that sex determination system in largemouth bass is male heterogametic (XX/XY). In this study, males and females genomic DNA pools were sequenced using a whole genomic sequencing approach. Using genome comparative analysis, we identified a large sex differentiated region (~ 1.7 Mb) at the beginning of chromosome 7 on largemouth bass. This non-recombination region contained enriched male-biased fragments and high-density of male-biased genetic polymorphisms. Meanwhile, sequence synteny analysis between/within sex chromosomes showed that many chromosomal rearrangement events have taken place in this region. Based on this genetic information, we successfully developed male specific genetic markers. Additionally, 96 genes were located on that sex differentiated region, whereas “usual suspects” sex determining gene didn't exist in this region. It is implied, in largemouth bass, a new gene has evolved as the master sex determining gene. Our results exhibited that largemouth bass has a large sex locus on Chromosome 7, which is likely the largemouth bass sex chromosome. The presence of numerous chromosomal rearrangements and the absence of “usual suspects” sex determining gene in this sex differentiated region indicate recombination is suppressed on that region and a new master sex determining gene may be co-opted in largemouth bass. Besides, we also developed sex-linked genetic markers. Our study will facilitate future researches on sex determination and aquaculture applications in largemouth bass.

Asymmetrical sex reversal: Does the type of heterogamety predict propensity for sex reversal?

Sex reversal, a mismatch between phenotypic and genetic sex, can be induced by chemical and thermal insults in ectotherms. Therefore, climate change and environmental pollution may increase sex-reversal frequency in wild populations, with wide-ranging implications for sex ratios, population dynamics, and the evolution of sex determination. We propose that reconsidering the half-century old theory "Witschi's rule" should facilitate understanding the differences between species in sex-reversal propensity and thereby predicting their vulnerability to anthropogenic environmental change. The idea is that sex reversal should be asymmetrical: more likely to occur in the homogametic sex, assuming that sex-reversed heterogametic individuals would produce new genotypes with reduced fitness. A review of the existing evidence shows that while sex reversal can be induced in both homogametic and heterogametic individuals, the latter seem to require stronger stimuli in several cases. We provide guidelines for future studies on sex reversal to facilitate data comparability and reliability.

Possible stochastic sex determination in Bursaphelenchus nematodes

Sex determination mechanisms evolve surprisingly rapidly, yet little is known in the large nematode phylum other than for Caenorhabditis elegans, which relies on chromosomal XX-XO sex determination and a dosage compensation mechanism. Here we analyze by sex-specific genome sequencing and genetic analysis sex determination in two fungal feeding/plant-parasitic Bursaphelenchus nematodes and find that their sex differentiation is more likely triggered by random, epigenetic regulation than by more well-known mechanisms of chromosomal or environmental sex determination. There is no detectable difference in male and female chromosomes, nor any linkage to sexual phenotype. Moreover, the protein sets of these nematodes lack genes involved in X chromosome dosage counting or compensation. By contrast, our genetic screen for sex differentiation mutants identifies a Bursaphelenchus ortholog of tra-1, the major output of the C. elegans sex determination cascade. Nematode sex determination pathways might have evolved by “bottom-up” accretion from the most downstream regulator, tra-1.

Screening and characterization of sex-linked DNA markers in Mozambique tilapia (Oreochromis mossambicus)

The Mozambique tilapia (Oreochromis mossambicus) is an important aquaculture fish. It shows sexual dimorphism in growth, with males growing much faster than females. Thus, production of all-male fingerlings of Mozambique tilapia would improve aquaculture efficiency. However, the lack of accurate sex-specific markers has hampered the mono-sex breeding and the study of the molecular mechanisms of sex determination in this species. Recently, we performed genome sequencing and re-sequencing of female and male Mozambique tilapia and identified the sex chromosome and sex determining region. In the present study, two sex-linked SNP markers were identified and validated. Male specific contigs were assembled from the unmapped reads after aligning male re-sequencing data against the published XX genome. Based on these male-specific contigs, three sex-linked DNA markers, Marker-1, Marker-2 and Marker-3, were developed and correctly identified the genetic sex of 16 fish. The universality of these three male-specific markers was then tested in a panel of 144 individuals, which showed a discrepancy of 5.5% (8/144) between genotypic sex and phenotypic sex. In conclusion, we developed three sex-linked markers to identify different sex genotypes in Mozambique tilapia. This study lays a foundation for the establishment of MAS-GMT (marker-assisted selection of genetically male tilapias) technique and sex-controlled breeding of Mozambique tilapia, as well as for the identification of the sex determining gene.

Physiologically-Based Pharmacokinetic Modeling to Predict Methylphenidate Exposure Affected by Interplay Among Carboxylesterase 1 Pharmacogenetics, Drug-Drug Interactions, and Sex

Background and objectiveThe pharmacokinetics (PK) of methylphenidate (MPH) differ significantly among individuals. Carboxylesterase 1 (CES1) is the primary enzyme metabolizing MPH, and its function is affected by genetic variants, drug-drug interaction (DDI), and sex. The object of this study is to evaluate CES1 pharmacogenetics as related to MPH metabolism using human liver samples and develop a physiologically-based pharmacokinetic (PBPK) modeling approach to investigate the influence of CES1 genotypes and other factors on MPH PK. MethodsThe effect of the CES1 variant G143E (rs71647871) on MPH metabolism was studied utilizing 102 individual human liver S9 (HLS9) fraction samples. PBPK models were developed using the population-based PBPK software PK-Sim® by incorporating the HLS9 incubation data. The established models were applied to simulate MPH PK profiles under various clinical scenarios, including different genotypes, drug-alcohol interactions, and the difference between males and females. ResultsThe HLS9 incubation study showed that subjects heterozygous for the CES1 variant G143E metabolized MPH at a rate of approximately 50% of that in non-carriers. The developed PBPK models successfully predicted the exposure alteration of MPH from the G143E genetic variant, ethanol-MPH DDI, and sex. Importantly, the study suggests that male G143E carriers who are alcohol consumers are at a higher risk of MPH overexposure. ConclusionPBPK modeling provides a means for better understanding the mechanisms underlying interindividual variability in MPH PK and PD and could be utilized to develop a safer and more effective MPH pharmacotherapy regimen.

Effect of BAY‐117082, a NLRP3 inflammasome inhibitor, in a mouse model of nitroglycerin (NTG)‐induced migraine

Migraine is a common brain disorder characterized by recurrent episodes of headache. It is a complex and multifactorial disease with a higher prevalence in females than in males. Several risk factors have been associated to migraine disease as genetic factors, sex and age. The pathophysiology of migraine is still unclear; however, it has been proven that NOD‐like receptor protein 3 (NLRP3) inflammasome pathway overactivation as well as p‐ERK/p‐CREB axis contribute to migraine pathogenesis. Therefore, the aim of this study was to investigate the effect of BAY‐117082, a NLRP3 inflammasome inhibitor and p‐ERK/p‐CREB modulator, in an in vivo model of nitroglycerin (NTG)‐induced migraine.Migraine model was induced by NTG intraperitoneal administration at dose of 10 mg/kg diluted in 0.9% saline. Mice were treated intraperitoneally with BAY‐117082 at doses of 1 mg/kg, 5 mg/kg, and 10 mg/kg, 5 minutes after NTG injection. Mice were sacrificed 4 h following NTG injection; the whole brain with the rostral spinal cord was removed to perform several analysis.Our results demonstrated that, following behavioral tests for pain and photophobia, BAY‐117082 treatment at doses of 5 mg/kg and 10 mg/kg reduced pain attacks induced by NTG more than BAY‐117082 at the dose of 1 mg/kg. Moreover, the treatment with BAY‐117082 at doses of 5 mg/kg and 10 mg/kg significantly reduced histological damage in the trigeminal nerve nucleus and significantly decreased inflammosome activation by reduction of NLRP3, ASC, IL‐1β and TNF‐α expression. Additionally, the treatment with BAY‐117082 at doses of 5 mg/kg and 10 mg/kg significantly modulated p‐ERK/p‐CREB axis activation through the reduction of p‐ERK, p‐AKT, p‐CREB and p‐PI3K expression.Therefore, the obtained results offer new insight into the role of NLRP3 inflammasome pathway and p‐ERK/p‐CREB axis in migraine pathogenesis, suggesting that BAY‐117082 could be considered a novel therapeutic strategy to treat migraine.