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Sex difference (SD) is ubiquitous in humans despite shared genetic architecture (SGA) between the sexes. A univariate approach, i.e., studying SD in single traits by estimating genetic correlation, does not provide a complete biological overview, because traits are not independent and are genetically correlated. The multivariate genetic architecture between the sexes can be summarized by estimating the additive genetic (co)variance across shared traits, which, apart from the cross-trait and cross-sex covariances, also includes the cross-sex-cross-trait covariances, e.g., between height in males and weight in females. Using such a multivariate approach, we investigated SD in the genetic architecture of 12 anthropometric, fat depositional, and sex-hormonal phenotypes. We uncovered sexual antagonism (SA) in the cross-sex-cross-trait covariances in humans, most prominently between testosterone and the anthropometric traits - a trend similar to phenotypic correlations. 27% of such cross-sex-cross-trait covariances were of opposite sign, contributing to asymmetry in the SGA. Intriguingly, using multivariate evolutionary simulations, we observed that the SGA acts as a genetic constraint to the evolution of SD in humans only when selection is sexually antagonistic and not concordant. Remarkably, we found that the lifetime reproductive success in both the sexes shows a positive genetic correlation with anthropometric traits, but not with testosterone. Moreover, we demonstrated that genetic variance is depleted along multivariate trait combinations in both the sexes but in different directions, suggesting absolute genetic constraint to evolution. Our results indicate that testosterone drives SA in contemporary humans and emphasize the necessity and significance of using a multivariate framework in studying SD.
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Fenotipo , Caracteres Sexuales , Testosterona , Humanos , Masculino , Femenino , Análisis MultivarianteRESUMEN
High-throughput sequencing (HTS) has revolutionized science by enabling super-fast detection of genomic variants at base-pair resolution. Consequently, it poses the challenging problem of identification of technical artifacts, i.e. hidden non-random error patterns. Understanding the properties of sequencing artifacts holds the key in separating true variants from false positives. Here, we develop Mapinsights, a toolkit that performs quality control (QC) analysis of sequence alignment files, capable of detecting outliers based on sequencing artifacts of HTS data at a deeper resolution compared with existing methods. Mapinsights performs a cluster analysis based on novel and existing QC features derived from the sequence alignment for outlier detection. We applied Mapinsights on community standard open-source datasets and identified various quality issues including technical errors related to sequencing cycles, sequencing chemistry, sequencing libraries and across various orthogonal sequencing platforms. Mapinsights also enables identification of anomalies related to sequencing depth. A logistic regression-based model built on the features of Mapinsights shows high accuracy in detecting 'low-confidence' variant sites. Quantitative estimates and probabilistic arguments provided by Mapinsights can be utilized in identifying errors, bias and outlier samples, and also aid in improving the authenticity of variant calls.
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Secuenciación de Nucleótidos de Alto Rendimiento , Programas Informáticos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Análisis de Secuencia de ADN/métodosRESUMEN
Clinical heterogeneity and varied prognosis are well noted for SARS-CoV-2 infection. Altered immune response is a major feature for the adverse prognosis however focus on altered immune response has been primarily limited to hyper-inflammatory responses like Cytokine storm. A deeper understanding of viral pathobiology and the interplay of innate and adaptive immune cells against SARS-CoV-2 infection is essential to optimize intervention strategy and future preparedness for SARS-CoV-2 or its related viral diseases. To uncover the immunological signatures driving the progression of SARS-CoV-2 infection, we performed an extensive immunophenotype on blood samples from 79 hospitalized patients with mild/moderate to severe infections as well as from healthy controls and recovered donors to understand the interplay between innate and adaptive responses impacting severity and prognosis. We observed multifarious immune dysregulation, varied across patients of the clinical spectrum. We observed 4 major dysregulations of immune phenotypes 1) depletion of M1φ (impaired antiviral response as APC), 2) immune suppression/exhaustion via activation of repressor like CD4+/CD8+PD1, TIM3, LAG3 3) inappropriate differentiation of lymphocyte (extreme elevated proportion of CD4 naive, memory B and T cells along with reduction of inflammatory activator like TLR2/4/TIGIT) and 4) cytokine storm. Our results show the identification of biomarkers to differentiate the different trajectories for SARS-CoV-2 infection.
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COVID-19 , Humanos , SARS-CoV-2 , Síndrome de Liberación de Citoquinas , Linfocitos T , InmunidadRESUMEN
Epidermolysis-Bullosa (EB), a rare Mendelian disorder, exhibits complex phenotypic and locus-heterogeneity. We identified a nuclear family of clinically unaffected parents with two offsprings manifesting EB-Pyloric-Atresia (EB-PA), with a variable clinical severity. We generated whole exome sequence data on all four individuals to (1) identify the causal mutation behind EB-PA (2) understand the background genetic variation for phenotype variability of the siblings. We assumed an autosomal recessive mode of inheritance and used suites of bioinformatic and computational tools to collate information through global databases to identify the causal genetic variant for the disease. We also investigated variations in key genes that are likely to impact phenotype severity. We identified a novel missense mutation in the ITGB4 gene (p.Ala1227Asp), for which the parents were heterozygous and the children homozygous. The mutation in ITGB4 gene, predicted to reduce the stability of the primary alpha6beta4-plectin complex compared to all previously studied mutations on ITGB4 reported to cause EB.
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Displasia Ectodérmica , Epidermólisis Ampollosa , Humanos , Plectina/genética , Mutación Missense/genética , Epidermólisis Ampollosa/genética , Displasia Ectodérmica/genética , Mutación , Integrina beta4/genéticaRESUMEN
BACKGROUND: The demographic history of South and Southeast Asia (S&SEA) is complex and contentious, with multiple waves of human migration. Some of the earliest footfalls were of the ancestors of modern Austroasiatic (AA) language speakers. Understanding the history of the AA language family, comprising of over 150 languages and their speakers distributed across broad geographical region in isolated small populations of various sizes, can help shed light on the peopling of S&SEA. Here we investigated the genetic relatedness of two AA groups, their relationship with other ethno-linguistically distinct populations, and the relationship of these groups with ancient genomes of individuals living in S&SEA at different time periods, to infer about the demographic history of this region. RESULTS: We analyzed 1451 extant genomes, 189 AAs from India and Malaysia, and 43 ancient genomes from S&SEA. Population structure analysis reveals neither language nor geography appropriately correlates with genetic diversity. The inconsistency between "language and genetics" or "geography and genetics" can largely be attributed to ancient admixture with East Asian populations. We estimated a pre-Neolithic origin of AA language speakers, with shared ancestry between Indian and Malaysian populations until about 470 generations ago, contesting the existing model of Neolithic expansion of the AA culture. We observed a spatio-temporal transition in the genetic ancestry of SEA with genetic contribution from East Asia significantly increasing in the post-Neolithic period. CONCLUSION: Our study shows that contrary to assumptions in many previous studies and despite having linguistic commonality, Indian AAs have a distinct genomic structure compared to Malaysian AAs. This linguistic-genetic discordance is reflective of the complex history of population migration and admixture shaping the genomic landscape of S&SEA. We postulate that pre-Neolithic ancestors of today's AAs were widespread in S&SEA, and the fragmentation and dissipation of the population have largely been a resultant of multiple migrations of East Asian farmers during the Neolithic period. It also highlights the resilience of AAs in continuing to speak their language in spite of checkered population distribution and possible dominance from other linguistic groups.
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Demografía , Genoma Humano , Pueblos Indígenas/genética , Lenguaje , Humanos , India , MalasiaRESUMEN
SIGNIFICANCE: A differential outcome in randomized controlled trials of anti-vascular endothelial growth factor (anti-VEGF) therapy, including ranibizumab, for diabetic macular edema is a major dilemma for planning, optimizing, and managing clinical usage. The variable outcome of the therapeutics necessitates the importance of finding a predictive biomarker for anti-VEGF therapy to improve subject selection. PURPOSE: Our study correlates the baseline pro- and anti-VEGF isoforms and its three receptors (VEGFReceptor1, VEGFReceptor2, and VEGFReceptor3) for circulatory candidate protein molecules among diabetic patients with macular edema, with the clinical outcome of ranibizumab therapy. METHODS: This study included 86 individuals who were anti-VEGF naive at the time of ascertainment but have completed the standardized therapy regimen of the clinic. Plasma proteins for pro- and anti-VEGF isoforms and its three receptors were determined in replicate by an enzyme-linked immunosorbent assay. RESULTS: The study demonstrated that 56 (65.12%) individuals benefited from the therapy in terms of letter gain (Snellen chart). Baseline plasma soluble VEGF receptor 2 (sVEGFR-2) was significantly higher among responders (65.10 pg/mL; 95% confidence interval, 55.41 to 74.80 pg/mL) compared with nonresponders (46.38 pg/mL; 95% confidence interval, 38.69 to 54.07 pg/mL; PFDR = .03). Diffuse diabetic macular edema with proliferative diabetic retinopathy increases the risk of nonresponse to the therapy by 3.03-fold (PFDR = .04). CONCLUSIONS: The present study postulates that diffuse diabetic macular edema with proliferative diabetic retinopathy and baseline circulatory soluble VEGF receptor 2 may be potential candidates as therapy-stratifying markers for ranibizumab treatment among patients with diabetic macular edema.
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Inhibidores de la Angiogénesis/uso terapéutico , Biomarcadores/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Retinopatía Diabética/tratamiento farmacológico , Edema Macular/tratamiento farmacológico , Ranibizumab/uso terapéutico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Retinopatía Diabética/sangre , Retinopatía Diabética/fisiopatología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inyecciones Intravítreas , Edema Macular/sangre , Edema Macular/fisiopatología , Masculino , Persona de Mediana Edad , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre , Receptor 2 de Factores de Crecimiento Endotelial Vascular/sangre , Receptor 3 de Factores de Crecimiento Endotelial Vascular/sangre , Agudeza Visual/fisiologíaRESUMEN
Obesity, a risk factor for multiple diseases (e.g. diabetes, hypertension, cancers) originates through complex interactions between genes and prevailing environment (food habit and lifestyle) that varies across populations. Indians exhibit a unique obesity phenotype with high abdominal adiposity for a given body weight compared to matched white populations suggesting presence of population-specific genetic and environmental factors influencing obesity. However, Indian population-specific genetic contributors for obesity have not been explored yet. Therefore, to identify potential genetic contributors, we performed a two-staged genome-wide association study (GWAS) for body mass index (BMI), a common measure to evaluate obesity in 5973 Indian adults and the lead findings were further replicated in 1286 Indian adolescents. Our study revealed novel association of variants-rs6913677 in BAI3 gene (p = 1.08 × 10-8) and rs2078267 in SLC22A11 gene (p = 4.62 × 10-8) at GWAS significance, and of rs8100011 in ZNF45 gene (p = 1.04 × 10-7) with near GWAS significance. As genetic loci may dictate the phenotype through modulation of epigenetic processes, we overlapped genetic data of identified signals with their DNA methylation patterns in 236 Indian individuals and performed methylation quantitative trait loci (meth-QTL) analysis. Further, functional roles of discovered variants and underlying genes were speculated using publicly available gene regulatory databases (ENCODE, JASPAR, GeneHancer, GTEx). The identified variants in BAI3 and SLC22A11 genes were found to dictate methylation patterns at unique CpGs harboring critical cis-regulatory elements. Further, BAI3, SLC22A11 and ZNF45 variants were located in repressive chromatin, active enhancer, and active chromatin regions, respectively, in human subcutaneous adipose tissue in ENCODE database. Additionally, these genomic regions represented potential binding sites for key transcription factors implicated in obesity and/or metabolic disorders. Interestingly, GTEx portal identify rs8100011 as a robust cis-expression quantitative trait locus (cis-eQTL) in subcutaneous adipose tissue (p = 1.6 × 10-7), and ZNF45 gene expression in skeletal muscle of Indian subjects showed an inverse correlation with BMI indicating its possible role in obesity. In conclusion, our study discovered 3 novel population-specific functional genetic variants (rs6913677, rs2078267, rs8100011) in 2 novel (SLC22A11 and ZNF45) and 1 earlier reported gene (BAI3) for BMI in Indians. Our study decodes key genomic loci underlying obesity phenotype in Indians that may serve as prospective drug targets in future.
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Estudio de Asociación del Genoma Completo , Factores de Transcripción de Tipo Kruppel/genética , Obesidad/genética , Transportadores de Anión Orgánico Sodio-Independiente/genética , Proteínas Represoras/genética , Adolescente , Adulto , Pueblo Asiatico/genética , Índice de Masa Corporal , Metilación de ADN , Femenino , Interacción Gen-Ambiente , Predisposición Genética a la Enfermedad , Humanos , Indígenas Norteamericanos/genética , Masculino , Obesidad/patología , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Adulto JovenRESUMEN
Background & objectives: Obesity-mediated chronic inflammatory state is primarily governed by lifestyle and food habits in adolescents and marked by alterations in the level of various inflammatory markers. This cross-sectional study was aimed to compare the inflammatory status of healthy Indian adolescents vis-à-vis their obesity profile. The inflammatory state of urban adolescents attending private and government-funded schools, and the relationship between inflammatory marker levels and anthropometric indices in the study participants from both groups were examined. Methods: A total of 4438 study participants (10-17 yr) were chosen from various schools of Delhi, India, and their anthropometric parameters were measured. Plasma adipocytokines (adiponectin, leptin and resistin) of the study participants were measured by enzyme-linked immunosorbent assay, and plasma C-reactive protein (CRP) levels were assayed by a biochemical analyzer. Metabolic syndrome-related risk factors such as waist circumference, hip circumference (HC), fasting glucose, fasting insulin, Homeostatic Model Assessment of Insulin Resistance, total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol and triglycerides of normal-weight adolescents were also evaluated. Results: The level of leptin and CRP increased with increasing adiposity, whereas adiponectin levels were found to be negatively related to obesity. All plasma cytokine levels (adiponectin, leptin and resistin) were significantly elevated in female than male adolescents. Age-based classification revealed a distinct trend of variability in the levels of all the inflammatory markers among adolescents of varying age groups. Significant differences were observed between private and government schoolgoing adolescents in terms of anthropometric and inflammatory parameters, with higher adiposity indices in the former group. The relationship of plasma adipokine and CRP levels with various adiposity indices was found to be distinctly different between private and government schoolgoing students. Interpretation & conclusions: Inflammatory markers were significantly elevated in overweight/obese adolescents. The socio-economic condition of urban Indian schoolgoing adolescents reflecting lifestyle transition has profound effects on their adiposity indices and inflammatory states. Longitudinal studies in different regions of the country need to be done to further confirm the findings.
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Biomarcadores/sangre , Inflamación/sangre , Obesidad/sangre , Obesidad Infantil/sangre , Adiponectina/sangre , Adolescente , Proteína C-Reactiva/metabolismo , Niño , Conducta Alimentaria , Femenino , Humanos , India/epidemiología , Leptina/sangre , Estilo de Vida , Masculino , Obesidad Infantil/epidemiología , Obesidad Infantil/patología , Resistina/sangre , Factores de RiesgoRESUMEN
INTRODUCTION AND OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is multistage with heterogeneous outcomes. We studied the influence of insulin resistance (IR) on the hepatic transcriptome of early NAFLD stages, to understand disease development. MATERIALS AND METHODS: In this cross-sectional study, possible clinicopathological risk factors were compared between mild-NAFL (Nâ¯=â¯72) and non-alcoholic steatohepatitis (NASH; Nâ¯=â¯51) patients. Liver tissue-transcriptome difference was studied between a subset of 25 mild-NAFL and 20 NASH biopsies and validated on another subset of 12 mild-NAFL and 13 NASH biopsies, using RT-PCR. The relationship between IR driven gene expression changes with fibrosis in NASH was investigated. RESULTS: Significantly higher weight (pâ¯=â¯0.005) and elevated levels of HbA1c (pâ¯=â¯0.009), FBG (pâ¯=â¯0.03) and HOMA-IR (pâ¯=â¯0.009) were found in NASH patients. Five differentially expressed genes (DEGs, fold changeâ¯>â¯1.5) were identified in NASH-FABP4, FABP5L2, CD24, PRAP1, and SPP1. The DEGs were positively associated with disease severity and HOMA-IR, and were found to be efficient classifiers of mild-NAFL and NASH. Additional 1218 genes identified related to IR (IrCGs), which can classify NASH-with-fibrosis patients separately from mild-NAFL and NASH patients. IrCGs can promote intra-hepatic fat accumulation, dysregulation of the lipid metabolism, lipotoxicity, and activation of cell survival pathways including activation of cell proliferation and differentiation pathways. CONCLUSIONS: Hepatic expression of genes associated with insulin resistance may drive NAFLD development and progression.
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Perfilación de la Expresión Génica , Resistencia a la Insulina/genética , Cirrosis Hepática/genética , Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Transcriptoma , Adulto , Glucemia/metabolismo , Antígeno CD24/genética , Antígeno CD24/metabolismo , Estudios Transversales , Progresión de la Enfermedad , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Insulina/sangre , Hígado/patología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Osteopontina/genética , Osteopontina/metabolismo , Proteínas Gestacionales/genética , Proteínas Gestacionales/metabolismo , Índice de Severidad de la EnfermedadRESUMEN
Lipids foster energy production and their altered levels have been coupled with metabolic ailments. Indians feature high prevalence of metabolic diseases, yet uncharacterized for genes regulating lipid homeostasis. We performed first GWAS for quantitative lipids (total cholesterol, LDL, HDL, and triglycerides) exclusively in 5271 Indians. Further to corroborate our genetic findings, we investigated DNA methylation marks in peripheral blood in Indians at the identified loci (N = 233) and retrieved gene regulatory features from public domains. Recurrent GWAS loci-CELSR2, CETP, LPL, ZNF259, and BUD13 cropped up as lead signals in Indians, reflecting their universal applicability. Besides established variants, we found certain unreported variants at sub-genome-wide level-QKI, REEP3, TMCC2, FAM129C, FAM241B, and LOC100506207. These variants though failed to attain GWAS significance in Indians, but largely turned out to be active CpG sites in human subcutaneous adipose tissue and showed robust association to two or more lipid traits. Of which, QKI variants showed significant association to all four lipid traits and their designated region was observed to be a key gene regulatory segment denoting active transcription particularly in human subcutaneous adipose tissue. Both established and novel loci were observed to be significantly associated with altered DNA methylation in Indians for specific CpGs that resided in key regulatory elements. Further, gene-based association analysis pinpointed novel GWAS loci-LINC01340 and IQCJ-SCHIP1 for TC; IFT27, IFT88, and LINC02141 for HDL; and TEX26 for TG. Present study ascertains universality of selected known genes and also identifies certain novel loci for lipids in Indians by integrating data from various levels of gene regulation.
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Colesterol/genética , Metilación de ADN/genética , Estudio de Asociación del Genoma Completo , Metabolismo de los Lípidos/genética , Adulto , Pueblo Asiatico/genética , Colesterol/sangre , HDL-Colesterol/sangre , HDL-Colesterol/genética , LDL-Colesterol/sangre , LDL-Colesterol/genética , Femenino , Humanos , India/epidemiología , Lípidos/sangre , Lípidos/genética , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo/genética , Grasa Subcutánea/crecimiento & desarrollo , Grasa Subcutánea/patología , Triglicéridos/sangre , Triglicéridos/genéticaRESUMEN
India, occupying the center stage of Paleolithic and Neolithic migrations, has been underrepresented in genome-wide studies of variation. Systematic analysis of genome-wide data, using multiple robust statistical methods, on (i) 367 unrelated individuals drawn from 18 mainland and 2 island (Andaman and Nicobar Islands) populations selected to represent geographic, linguistic, and ethnic diversities, and (ii) individuals from populations represented in the Human Genome Diversity Panel (HGDP), reveal four major ancestries in mainland India. This contrasts with an earlier inference of two ancestries based on limited population sampling. A distinct ancestry of the populations of Andaman archipelago was identified and found to be coancestral to Oceanic populations. Analysis of ancestral haplotype blocks revealed that extant mainland populations (i) admixed widely irrespective of ancestry, although admixtures between populations was not always symmetric, and (ii) this practice was rapidly replaced by endogamy about 70 generations ago, among upper castes and Indo-European speakers predominantly. This estimated time coincides with the historical period of formulation and adoption of sociocultural norms restricting intermarriage in large social strata. A similar replacement observed among tribal populations was temporally less uniform.
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Etnicidad/genética , Genética de Población , Genoma Humano , Filogenia , Pool de Genes , Variación Genética , Genotipo , Geografía , Humanos , India , Islas , Lingüística , Modelos Genéticos , Análisis de Componente Principal , Factores de TiempoRESUMEN
Phenotypic characteristics are known to vary substantially among different ethnicities around the globe. These variations are mediated by number of stochastic events and cannot be attributed to genetic architecture alone. DNA methylation is a well-established mechanism that sculpts our epigenome influencing phenotypic variation including disease manifestation. Since DNA methylation is an important determinant for health issues of a population, it demands a thorough investigation of the natural differences in genome wide DNA methylation patterns across different ethnic groups. This study is based on comparative analyses of methylome from five different ethnicities with major focus on Indian subjects. The current study uses hierarchical clustering approaches, principal component analysis and locus specific differential methylation analysis on Illumina 450K methylation data to compare methylome of different ethnic subjects. Our data indicates that the variations in DNA methylation patterns of Indians are less among themselves compared to other global population. It empirically correlated with dietary, cultural and demographical divergences across different ethnic groups. Our work further suggests that Indians included in this study, despite their genetic similarity with the Caucasian population, are in close proximity with Japanese in terms of their methylation signatures.
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Mapeo Cromosómico , Islas de CpG/genética , Metilación de ADN/genética , ADN/análisis , Etnicidad/genética , Adulto , Análisis por Conglomerados , ADN/metabolismo , Epigénesis Genética , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , FenotipoRESUMEN
Identification and study of genetic variation in recently admixed populations not only provides insight into historical population events but also is a powerful approach for mapping disease loci. We studied a population (OG-W-IP) that is of African-Indian origin and has resided in the western part of India for 500 years; members of this population are believed to be descendants of the Bantu-speaking population of Africa. We have carried out this study by using a set of 18,534 autosomal markers common between Indian, CEPH-HGDP, and HapMap populations. Principal-components analysis clearly revealed that the African-Indian population derives its ancestry from Bantu-speaking west-African as well as Indo-European-speaking north and northwest Indian population(s). STRUCTURE and ADMIXTURE analyses show that, overall, the OG-W-IPs derive 58.7% of their genomic ancestry from their African past and have very little inter-individual ancestry variation (8.4%). The extent of linkage disequilibrium also reveals that the admixture event has been recent. Functional annotation of genes encompassing the ancestry-informative markers that are closer in allele frequency to the Indian ancestral population revealed significant enrichment of biological processes, such as ion-channel activity, and cadherins. We briefly examine the implications of determining the genetic diversity of this population, which could provide opportunities for studies involving admixture mapping.
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Población Negra/genética , Variación Genética , Genética de Población/estadística & datos numéricos , Población Blanca/genética , África Occidental , Alelos , Bases de Datos Genéticas , Frecuencia de los Genes , Marcadores Genéticos , Genotipo , Humanos , India , Desequilibrio de LigamientoRESUMEN
While the population-based case-control approach is the popular study design for association mapping of complex genetic traits because of ease of data collection and statistical analyses, it suffers from the inherent problem of population stratification. There have been methodological developments for adjusting these studies for population substructure, but efficient estimation of the number of subpopulations (K), which has evolutionary significance, remains a statistical challenge. In this article, we propose a Bayesian semiparametric approach to estimate population substructure under the assumption that K is random. Using extensive simulations, we find that our proposed method is not only computationally much faster than an existing Bayesian approach Structure, but also estimates the number of subpopulations more accurately, and thus, yields more power in detecting association in case-control studies.
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Teorema de Bayes , Estudios de Casos y Controles , Genética de Población/métodos , Estudio de Asociación del Genoma Completo/métodos , Modelos Genéticos , Algoritmos , Análisis por Conglomerados , Simulación por Computador , Variación Genética , Humanos , Polimorfismo de Nucleótido SimpleRESUMEN
It is believed that establishment of the gut microbiome starts very early in life and is crucial for growth, immunity, and long-term metabolic health. In this longitudinal study, we recruited 25 mothers in their third trimester, of whom 15 had vaginal delivery while 10 had an unplanned cesarean section (C-section). The mother-neonate pairs were followed for 1 year, and we generated 16S metagenomic data to study the neonatal gut microbiome along with mother's breast milk and vaginal microbiomes through 12 months after delivery, at 1, 3, 6, and 12 months. We inferred (i) mode of delivery is an important factor influencing both composition and entropy of the neonatal gut microbiome, and the genus Streptococcus plays an important role in the temporal differentiation. (ii) Microbial diversity monotonically increases with age, irrespective of the mode of delivery, and it is significantly altered once exclusive breastfeeding is stopped. (iii) We found little evidence in favor of the microflora of mother's breast milk and a vaginal swab being directly reflected in the offspring's gut microbiome; however, some distinction could be made in the gut microbiome of neonates whose mothers were classified as community state type III (CSTIII) and CSTIV, based on their vaginal microbiomes. (iv) A lot of the mature gut microbiome is possibly acquired from the environment, as the genera Prevotella and Faecalibacterium, two of the most abundant flora in the neonatal gut microbiome, are introduced after initiation of solidified food. The distinction between the gut microbiome of babies born by vaginal delivery and babies born by C-section becomes blurred after introduction of solid food, although the diversity in the gut microbiota drastically increases in both cases. IMPORTANCE Gut microbiome architecture seems to have a potential impact on host metabolism, health, and nutrition. Early life gut microbiome development is considered a crucial phenomenon for neonatal health as well as adulthood metabolic complications. In this longitudinal study, we examined the association of neonatal gut microbiome entropy and its temporal variation. The study revealed that adult-like gut microbiome architecture starts taking shape after initiation of solidified food. Further, we also observed that the difference of microbial diversity was reduced between vaginally delivered and C-section babies compared to exclusive breastfeeding tenure. We found evidence in favor of the inheritance of the microflora of mother's posterior vaginal wall to the offspring's gut microbiome.
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Microbioma Gastrointestinal , Microbiota , Lactante , Recién Nacido , Adulto , Humanos , Embarazo , Femenino , Cesárea , Leche Humana , Estudios LongitudinalesRESUMEN
IMPORTANCE: The role of the upper respiratory tract (URT) microbiome in predicting lung health has been documented in several studies. The dysbiosis in COVID patients has been associated with disease outcomes by modulating the host immune system. However, although it has been known that different SARS-CoV-2 variants manifest distinct transmissibility and mortality rates in human populations, their effect on the composition and diversity of the URT microbiome has not been studied to date. Unlike the older variant (Delta), the newer variant (Omicron) have become more transmissible with lesser mortality and the symptoms have also changed significantly. Hence, in the present study, we have investigated the change in the URT microbiome associated with Delta and Omicron variants and identified variant-specific signatures that will be useful in the assessment of lung health and can be utilized for nasal probiotic therapy in the future.
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COVID-19 , Microbiota , Humanos , SARS-CoV-2/genética , Microbiota/genética , NarizRESUMEN
Sarcoglycanopathy is the most frequent form of autosomal recessive limb-girdle muscular dystrophies caused by mutations in SGCB gene encoding beta-sarcoglycan proteins. In this study, we describe a shared, common haplotype co-segregating in 14 sarcoglycanopathy cases from 13 unrelated families from south Indian region with the likely pathogenic homozygous mutation c.544 T > G (p.Thr182Pro) in SGCB. Haplotype was reconstructed based on 10 polymorphic markers surrounding the c.544 T > G mutation in the cases and related family members as well as 150 unrelated controls from Indian populations using PLINK1.9. We identified haplotype H1 = G, A, G, T, G, G, A, C, T, G, T at a significantly higher frequency in cases compared to related controls and unrelated control Indian population. Upon segregation analysis within the family pedigrees, H1 is observed to co-segregate with c.544 T > G in a homozygous state in all the pedigrees of cases except one indicating a probable event of founder effect. Furthermore, Identical-by-descent and inbreeding coefficient analysis revealed relatedness among 33 new pairs of seemingly unrelated individuals from sarcoglycanopathy cohort and a higher proportion of homozygous markers, thereby indicating common ancestry. Since all these patients are from the south Indian region, we suggest this region to be a primary target of mutation screening in patients diagnosed with sarcoglycanopathy.
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Sarcoglicanopatías , Sarcoglicanos , Humanos , Pueblo Asiatico , Haplotipos , Mutación , Sarcoglicanopatías/genética , Sarcoglicanos/genéticaRESUMEN
Absolute pitch (AP) is the rare ability to instantaneously recognize and label tones with their musical note names without using a reference pitch for comparison. The etiology of AP is complex. Prior studies have implicated both genetic and environmental factors in its genesis, yet the molecular basis for AP remains unknown. To locate regions of the human genome that may harbor AP-predisposing genetic variants, we performed a genome-wide linkage study on 73 multiplex AP families by genotyping them with 6090 SNP markers. Nonparametric multipoint linkage analyses were conducted, and the strongest evidence for linkage was observed on chromosome 8q24.21 in the subset of 45 families with European ancestry (exponential LOD score = 3.464, empirical genome-wide p = 0.03). Other regions with suggestive LOD scores included chromosomes 7q22.3, 8q21.11, and 9p21.3. Of these four regions, only the 7q22.3 linkage peak was also evident when 19 families with East Asian ancestry were analyzed separately. Though only one of these regions has yet reached statistical significance individually, we detected a larger number of independent linkage peaks than expected by chance overall, indicating that AP is genetically heterogeneous.