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1.  c.*84G>A Mutation in CETP Is Associated with Coronary Artery Disease in South Indians 
PLoS ONE  2016;11(10):e0164151.
Coronary artery disease (CAD) is one of the leading causes of mortality worldwide. It is a multi-factorial disease and several studies have demonstrated that the genetic factors play a major role in CAD. Although variations in cholesteryl ester transfer protein (CETP) gene are reported to be associated with CAD, this gene has not been studied in South Indian populations. Hence we evaluated the CETP gene variations in CAD patients of South Indian origin.
We sequenced all the exons, exon-intron boundaries and UTRs of CETP in 323 CAD patients along with 300 ethnically and age matched controls. Variations observed in CETP were subjected to various statistical analyses.
Results and Discussion
Our analysis revealed a total of 13 variations. Of these, one3’UTRvariant rs1801706 (c.*84G>A) was significantly associated with CAD (genotype association test: OR = 2.16, 95% CI: 1.50–3.10, p = 1.88x10-5 and allelic association test: OR = 1.92, 95% CI: 1.40–2.63, p = 2.57x10-5). Mutant allele “A” was observed to influence the higher concentration of mRNA (p = 7.09×10−3, R2 = 0.029 and β = 0.2163). Since expression of CETP has been shown to be positively correlated with the risk of CAD, higher frequency of “A” allele (patients: 22.69% vs.controls: 13%) reveals that c.*84G>A is a risk factor for CAD in South Indians.
This is the first report of the CETP gene among South Indians CAD patients. Our results suggest that rs1801706 (c.*84G>A) is a risk factor for CAD in South Indian population.
PMCID: PMC5074517  PMID: 27768712
2.  Cryptic Eimeria genotypes are common across the southern but not northern hemisphere☆ 
Graphical abstract
•The seven Eimeria spp. recognised to infect chickens are present globally.•Cryptic Eimeria operational taxonomic units (OTUs) are common in the southern but not northern hemisphere.•Parasite population structure appears to vary between Eimeria spp.
The phylum Apicomplexa includes parasites of medical, zoonotic and veterinary significance. Understanding the global distribution and genetic diversity of these protozoa is of fundamental importance for efficient, robust and long-lasting methods of control. Eimeria spp. cause intestinal coccidiosis in all major livestock animals and are the most important parasites of domestic chickens in terms of both economic impact and animal welfare. Despite having significant negative impacts on the efficiency of food production, many fundamental questions relating to the global distribution and genetic variation of Eimeria spp. remain largely unanswered. Here, we provide the broadest map yet of Eimeria occurrence for domestic chickens, confirming that all the known species (Eimeria acervulina, Eimeria brunetti, Eimeria maxima, Eimeria mitis, Eimeria necatrix, Eimeria praecox, Eimeria tenella) are present in all six continents where chickens are found (including 21 countries). Analysis of 248 internal transcribed spacer sequences derived from 17 countries provided evidence of possible allopatric diversity for species such as E. tenella (FST values ⩽0.34) but not E. acervulina and E. mitis, and highlighted a trend towards widespread genetic variance. We found that three genetic variants described previously only in Australia and southern Africa (operational taxonomic units x, y and z) have a wide distribution across the southern, but not the northern hemisphere. While the drivers for such a polarised distribution of these operational taxonomic unit genotypes remains unclear, the occurrence of genetically variant Eimeria may pose a risk to food security and animal welfare in Europe and North America should these parasites spread to the northern hemisphere.
PMCID: PMC4978698  PMID: 27368611
Eimeria; Chicken; Genetic diversity; Operational taxonomic units; Vaccine
3.  Whole Exome Screening Identifies Novel and Recurrent WISP3 Mutations Causing Progressive Pseudorheumatoid Dysplasia in Jammu and Kashmir-India 
Scientific Reports  2016;6:27684.
We report identification and genetic characterization of a rare skeletal disorder that remained unidentified for decades in a village of Jammu and Kashmir, India. The population residing in this region is highly consanguineous and a lack of understanding of the disorder has hindered clinical management and genetic counseling for the many affected individuals in the region. We collected familial information and identified two large extended multiplex pedigrees displaying apparent autosomal recessive inheritance of an uncharacterized skeletal dysplasia. Whole exome sequencing (WES) in members of one pedigree revealed a rare mutation in WISP3:c.156C > A (NP_003871.1:p.Cys52Ter), that perfectly segregated with the disease in the family. To our surprise, Sanger sequencing the WISP3 gene in the second family identified a distinct, novel splice site mutation c.643 + 1G > A, that perfectly segregated with the disease. Combining our next generation sequencing data with careful clinical documentation (familial histories, genetic data, clinical and radiological findings), we have diagnosed the families with Progressive Pseudorheumatoid Dysplasia (PPD). Our results underscore the utility of WES in arriving at definitive diagnoses for rare skeletal dysplasias. This genetic characterization will aid in genetic counseling and management, critically required to curb this rare disorder in the families.
PMCID: PMC4904372  PMID: 27291587
5.  Mitochondrial DNA variations in Madras motor neuron disease 
Mitochondrion  2013;13(6):721-728.
Although the Madras Motor Neuron Disease (MMND) was found three decades ago, its genetic basis has not been elucidated, so far. The symptom at onset was impaired hearing, upper limb weakness and atrophy. Since some clinical features of MMND overlap with mitochondrial disorders, we analyzed the complete mitochondrial genome of 45 MMND patients and found 396 variations, including 13 disease-associated, 2 mt-tRNA and 33 non-synonymous (16 MT-ND, 10 MT-CO, 3 MT-CYB and 4 MT-ATPase). A rare variant (m.8302A>G) in mt-tRNALeu was found in three patients. We predict that these variation(s) may influence the disease pathogenesis along with some unknown factor(s).
PMCID: PMC4805120  PMID: 23419391
MMND; deafness; mitochondria; mtDNA; tRNA; haplogroup
6.  Is MTHFR 677 C>T Polymorphism Clinically Important in Polycystic Ovarian Syndrome (PCOS)? A Case-Control Study, Meta-Analysis and Trial Sequential Analysis 
PLoS ONE  2016;11(3):e0151510.
Optimum efficiency of the folate pathway is considered essential for adequate ovarian function. 677 C>T substitution in the 5, 10-methylene tertrahydrofolatereductase (MTHFR) gene compromises activity of the MTHFR enzyme by about 50%. The significance of correlation between 677C>T substitution and PCOS remains dubious due to the low power of published studies.
Methods and Results
We analyzed MTHFR 677 C>T site in ethnically two different PCOS case-control groups (total 261 cases and 256 controls) from India. The data analysis revealed a lack of association between this polymorphism and PCOS [OR = 1.11 (95%CI = 0.71–1.72), P = 0.66]. Group-wise analysis on the basis of ethnicity also revealed no association in any of the ethnic groups [Indo-Europeans, P = 1; Dravidians, P = 0.70]. Homocysteine levels did not differ significantly between cases (15.51 μmol/L, SD = 2.89) and controls (15.89 μmol/L, SD = 2.23). We also undertook a meta-analysis on 960 cases and 1028 controls, which suggested a significant association of the substitution with PCOS in the dominant model of analysis (OR = 1.47 (95%CI = 1.04–2.09), P = 0.032]. Trial sequential analysis corroborated findings of the traditional meta-analysis. However, we found that the conclusions of meta-analysis were strongly influenced by studies that deviated from the Hardy Weinberg equilibrium. A careful investigation of each study and a trial sequential analysis suggested that 677 C>T substitution holds no clinical significance in PCOS in most of the populations.
In conclusion, MTHFR 677 C>T polymorphism does not affect PCOS risk in India. The association seen in the meta-analysis is due to an outlier study and studies showing deviation from the Hardy Weinberg equilibrium.
PMCID: PMC4794143  PMID: 26983014
7.  Genetic affinities of the Jewish populations of India 
Scientific Reports  2016;6:19166.
Due to the lack of written records or inscription, the origin and affiliation of Indian Jewish populations with other world populations remain contentious. Previous genetic studies have found evidence for a minor shared ancestry of Indian Jewish with Middle Eastern (Jewish) populations. However, these studies (relied on limited individuals), haven’t explored the detailed temporal and spatial admixture process of Indian Jewish populations with the local Indian populations. Here, using large sample size with combination of high resolution biparental (autosomal) and uniparental markers (Y chromosome and mitochondrial DNA), we reconstructed genetic history of Indian Jewish by investigating the patterns of genetic diversity. Consistent with the previous observations, we detected minor Middle Eastern specific ancestry component among Indian Jewish communities, but virtually negligible in their local neighbouring Indian populations. The temporal test of admixture suggested that the first admixture of migrant Jewish populations from Middle East to South India (Cochin) occurred during fifth century. Overall, we concluded that the Jewish migration and admixture in India left a record in their genomes, which can link them to the ‘Jewish Diaspora’.
PMCID: PMC4725824  PMID: 26759184
8.  Dissecting the influence of Neolithic demic diffusion on Indian Y-chromosome pool through J2-M172 haplogroup 
Scientific Reports  2016;6:19157.
The global distribution of J2-M172 sub-haplogroups has been associated with Neolithic demic diffusion. Two branches of J2-M172, J2a-M410 and J2b-M102 make a considerable part of Y chromosome gene pool of the Indian subcontinent. We investigated the Neolithic contribution of demic dispersal from West to Indian paternal lineages, which majorly consists of haplogroups of Late Pleistocene ancestry. To accomplish this, we have analysed 3023 Y-chromosomes from different ethnic populations, of which 355 belonged to J2-M172. Comparison of our data with worldwide data, including Y-STRs of 1157 individuals and haplogroup frequencies of 6966 individuals, suggested a complex scenario that cannot be explained by a single wave of agricultural expansion from Near East to South Asia. Contrary to the widely accepted elite dominance model, we found a substantial presence of J2a-M410 and J2b-M102 haplogroups in both caste and tribal populations of India. Unlike demic spread in Eurasia, our results advocate a unique, complex and ancient arrival of J2a-M410 and J2b-M102 haplogroups into Indian subcontinent.
PMCID: PMC4709632  PMID: 26754573
9.  Genotype–phenotype correlation in long QT syndrome families 
Heterogeneity in clinical manifestations is a well-known feature in Long QT Syndrome (LQTS). The extent of this phenomenon became evident in families wherein both symptomatic and asymptomatic family members are reported. The study hence warrants genetic testing and/or screening of family members of LQTS probands for risk stratification and prediction.
Of the 46 families screened, 18 probands revealed novel variations/compound heterozygosity in the gene/s screened. Families 1–4 revealed probands carrying novel variations in KCNQ1 gene along with compound heterozygosity of risk genotypes of the SCN5A, KCNE1 and NPPA gene/s polymorphisms screened. It was also observed that families- 5, 6 and 7 were typical cases of “anticipation” in which both mother and child were diagnosed with congenital LQTS (cLQTS). Families- 16 and 17 represented aLQTS probands with variations in IKs and INa encoding genes. First degree relatives (FDRs) carrying the same haplotype as the proband were also identified which may help in predictive testing and management of LQTS. Most of the probands exhibiting a family history were found to be genetic compounds which clearly points to the role of cardiac genes and their modifiers in a recessive fashion in LQTS manifestation.
PMCID: PMC4867973  PMID: 27479201
LQTS; Compound heterozygosity; Common haplotype; Family study
10.  Unravelling the distinct strains of Tharu ancestry 
European Journal of Human Genetics  2014;22(12):1404-1412.
The northern region of the Indian subcontinent is a vast landscape interlaced by diverse ecologies, for example, the Gangetic Plain and the Himalayas. A great number of ethnic groups are found there, displaying a multitude of languages and cultures. The Tharu is one of the largest and most linguistically diverse of such groups, scattered across the Tarai region of Nepal and bordering Indian states. Their origins are uncertain. Hypotheses have been advanced postulating shared ancestry with Austroasiatic, or Tibeto-Burman-speaking populations as well as aboriginal roots in the Tarai. Several Tharu groups speak a variety of Indo-Aryan languages, but have traditionally been described by ethnographers as representing East Asian phenotype. Their ancestry and intra-population diversity has previously been tested only for haploid (mitochondrial DNA and Y-chromosome) markers in a small portion of the population. This study presents the first systematic genetic survey of the Tharu from both Nepal and two Indian states of Uttarakhand and Uttar Pradesh, using genome-wide SNPs and haploid markers. We show that the Tharu have dual genetic ancestry as up to one-half of their gene pool is of East Asian origin. Within the South Asian proportion of the Tharu genetic ancestry, we see vestiges of their common origin in the north of the South Asian Subcontinent manifested by mitochondrial DNA haplogroup M43.
PMCID: PMC4231405  PMID: 24667789
11.  Genome-wide analysis correlates Ayurveda Prakriti 
Scientific Reports  2015;5:15786.
The practice of Ayurveda, the traditional medicine of India, is based on the concept of three major constitutional types (Vata, Pitta and Kapha) defined as “Prakriti”. To the best of our knowledge, no study has convincingly correlated genomic variations with the classification of Prakriti. In the present study, we performed genome-wide SNP (single nucleotide polymorphism) analysis (Affymetrix, 6.0) of 262 well-classified male individuals (after screening 3416 subjects) belonging to three Prakritis. We found 52 SNPs (p ≤ 1 × 10−5) were significantly different between Prakritis, without any confounding effect of stratification, after 106 permutations. Principal component analysis (PCA) of these SNPs classified 262 individuals into their respective groups (Vata, Pitta and Kapha) irrespective of their ancestry, which represent its power in categorization. We further validated our finding with 297 Indian population samples with known ancestry. Subsequently, we found that PGM1 correlates with phenotype of Pitta as described in the ancient text of Caraka Samhita, suggesting that the phenotypic classification of India’s traditional medicine has a genetic basis; and its Prakriti-based practice in vogue for many centuries resonates with personalized medicine.
PMCID: PMC4625161  PMID: 26511157
12.  Mutational analysis of SCN5A gene in long QT syndrome 
Meta Gene  2015;6:26-35.
The SCN5A gene encodes for the INa channel implicated in long QT syndrome type-3 (LQTS-type-3). Clinical symptoms of this type are lethal as most patients had a sudden death during sleep. Screening of SCN5A in South Indian cohort by PCR-SSCP analyses revealed five polymorphisms — A29A (exon-2), H558R (exon-12), E1061E and S1074R (exon-17) and IVS25 + 65G > A (exon-25) respectively. In-silico and statistical analyses were performed on all the polymorphisms.
Exon-2 of SCN5A gene revealed A282G polymorphism (rs6599230), resulting in alanine for alanine (A29A) silent substitution in the N-terminus of SCN5A protein. Exon-12 showed A1868G polymorphism (H558R — rs1805124) and its ‘AA’ genotype and ‘A’ allele frequency were found to be higher in LQTS patients pointing towards its role in LQTS etiology.
Two polymorphisms A3378G (E1061E) and the novel C3417A (S1074R) were identified as compound heterozygotes/genetic compounds in exon-17 of SCN5A located in the DIIS6–DIIIS1 domain of the SCN5A transmembrane protein. IVS25 + 65G > A was identified in intron-25 of SCN5A. The ‘G’ allele was identified as the risk allele.
Variations were identified in in-silico analyses which revealed that these genetic compounds may lead to downstream signaling variations causing aberrations in sodium channel functions leading to prolonged QTc. The compound heterozygotes of SCN5A gene polymorphisms revealed a significant association which may be deleterious/lethal leading to an aberrant sodium ion channel causing prolonged QTc.
•Screening of SCN5A in South Indian cohort showed 4 reported and 1 novel polymorphism.•Compound heterozygotes found to have a significant association with LQTS•Genetic compounds maybe deleterious leading to an aberrant sodium ion channel
PMCID: PMC4561237  PMID: 26401487
LQTS, Long QT syndrome; cLQTS, Congenital long QT syndrome; FDRs, First degree relatives; LQT3, Long QT syndrome type-3; SCN5A, Sodium channel, voltage-gated, type V, alpha subunit; LQTS; SCN5A; Polymorphisms; Compound heterozygotes
13.  RAF1 mutations in childhood-onset dilated cardiomyopathy 
Nature genetics  2014;46(6):635-639.
Dilated cardiomyopathy (DCM) is a highly heterogeneous trait with sarcomeric gene mutations predominating. The cause of a significant percentage of DCM remains unknown and no gene-specific therapy is available. Based on resequencing with 513 DCM cases and 1,150 matched controls from various ethnically distinct cohorts, we discovered rare, functional RAF1 mutations in three of them (South India, North India and Japan). The prevalence of RAF1 mutations was ~9% in childhood-onset DCM cases in those three cohorts. Biochemical studies showed that DCM-associated RAF1 mutants had altered kinase activity, resulting in largely unaltered ERK activation but AKT that was hyperactivated in a BRAF-dependent manner. Constitutive expression of these mutants in zebrafish embryos resulted in a heart failure phenotype with AKT hyperactivation that was rescued by rapamycin treatment. These findings provide new mechanistic insights and potential therapeutic targets for RAF1-associated DCM and further expand the clinical spectrum of RAF1-related human disorders.
PMCID: PMC4049514  PMID: 24777450
14.  Propagation of pure fetal and maternal mesenchymal stromal cells from terminal chorionic villi of human term placenta 
Scientific Reports  2015;5:10054.
Long term propagation of human fetal mesenchymal stromal cells (MSC) in vitro has proven elusive due to limited availability of fetal tissue sources and lack of appropriate methodologies. Here, we have demonstrated the presence of fetal and maternal cells within the tips of terminal chorionic villi (TCV) of normal human term placenta, and we have exploited inherent differences in the adhesive and migratory properties of maternal vs. fetal cells, to establish pure MSC cultures of both cell types. The origin and purity of each culture was confirmed by X-Y chromosome-specific fluorescence in situ hybridization (FISH) and short tandem repeat (STR) genotyping. This is the first demonstration of fetal and maternal cells in the TCV of human term placenta and also of deriving pure fetal MSC cultures from them. The concomitant availability of pure cultures of adult and fetal MSC from one tissue provides a good system to compare genetic and epigenetic differences between adult and fetal MSCs; and also to generate new models of cell based therapies in regenerative medicine.
PMCID: PMC4432313  PMID: 25975441
15.  Association of Ficolin-2 Serum Levels and FCN2 Genetic Variants with Indian Visceral Leishmaniasis 
PLoS ONE  2015;10(5):e0125940.
Visceral leishmaniasis (VL), one of the neglected tropical diseases, is endemic in the Indian subcontinent. Ficolins are circulating serum proteins of the lectin complement system and involved in innate immunity.
We have estimated ficolin-2 serum levels and analyzed the functional variants of the encoding gene FCN2 in 218 cases of VL and in 225 controls from an endemic region of India.
Elevated levels of serum ficolin-2 were observed in VL cases compared to the controls (adjusted P<0.0001). The genetic analysis revealed that the FCN2 structural variant +6359 C>T (p.T236M) was associated with VL (OR=2.2, 95% CI=1.23-7.25, P=0.008) and with high ficolin-2 serum levels. We also found that the FCN2*AAAC haplotype occurred more frequently among healthy controls when compared to cases (OR=0.59, 95%CI=0.37-0.94, P=0.023).
Our findings indicate that the FCN2 variant +6359C>T is associated with the occurrence of VL and that ficolin-2 serum levels are elevated in Leishmania infections.
PMCID: PMC4428791  PMID: 25965808
16.  DNA methylation analysis of phenotype specific stratified Indian population 
DNA methylation and its perturbations are an established attribute to a wide spectrum of phenotypic variations and disease conditions. Indian traditional system practices personalized medicine through indigenous concept of distinctly descriptive physiological, psychological and anatomical features known as prakriti. Here we attempted to establish DNA methylation differences in these three prakriti phenotypes.
Following structured and objective measurement of 3416 subjects, whole blood DNA of 147 healthy male individuals belonging to defined prakriti (Vata, Pitta and Kapha) between the age group of 20-30years were subjected to methylated DNA immunoprecipitation (MeDIP) and microarray analysis. After data analysis, prakriti specific signatures were validated through bisulfite DNA sequencing.
Differentially methylated regions in CpG islands and shores were significantly enriched in promoters/UTRs and gene body regions. Phenotypes characterized by higher metabolism (Pitta prakriti) in individuals showed distinct promoter (34) and gene body methylation (204), followed by Vata prakriti which correlates to motion showed DNA methylation in 52 promoters and 139 CpG islands and finally individuals with structural attributes (Kapha prakriti) with 23 and 19 promoters and CpG islands respectively. Bisulfite DNA sequencing of prakriti specific multiple CpG sites in promoters and 5′-UTR such as; LHX1 (Vata prakriti), SOX11 (Pitta prakriti) and CDH22 (Kapha prakriti) were validated. Kapha prakriti specific CDH22 5′-UTR CpG methylation was also found to be associated with higher body mass index (BMI).
Differential DNA methylation signatures in three distinct prakriti phenotypes demonstrate the epigenetic basis of Indian traditional human classification which may have relevance to personalized medicine.
Electronic supplementary material
The online version of this article (doi:10.1186/s12967-015-0506-0) contains supplementary material, which is available to authorized users.
PMCID: PMC4438459  PMID: 25952924
DNA methylation; MeDIP; CpG Island; Prakriti; Ayurveda
17.  IL10 Variant g.5311A Is Associated with Visceral Leishmaniasis in Indian Population 
PLoS ONE  2015;10(5):e0124559.
Visceral leishmaniasis (VL) is a multifactorial disease, where the host genetics play a significant role in determining the disease outcome. The immunological role of anti-inflammatory cytokine, Interleukin 10 (IL10), has been well-documented in parasite infections and considered as a key regulatory cytokine for VL. Although VL patients in India display high level of IL10 in blood serum, no genetic study has been conducted to assess the VL susceptibility / resistance. Therefore, the aim of this study is to investigate the role of IL10 variations in Indian VL; and to estimate the distribution of disease associated allele in diverse Indian populations.
All the exons and exon-intron boundaries of IL10 were sequenced in 184 VL patients along with 172 ethnically matched controls from VL endemic region of India.
Result and Discussion
Our analysis revealed four variations; rs1518111 (2195 A>G, intron), rs1554286 (2607 C>T, intron), rs3024496 (4976 T>C, 3’ UTR) and rs3024498 (5311 A>G, 3’ UTR). Of these, a variant g.5311A is significantly associated with VL (χ2=18.87; p =0.00001). In silico approaches have shown that a putative micro RNA binding site (miR-4321) is lost in rs3024498 mRNA. Further, analysis of the above four variations in 1138 individuals from 34 ethnic populations, representing different social and linguistic groups who are inhabited in different geographical regions of India, showed variable frequency. Interestingly, we have found, majority of the tribal populations have low frequency of VL (‘A’ of rs3024498); and high frequency of leprosy (‘T’ of rs1554286), and Behcet’s (‘A’ of rs1518111) associated alleles, whereas these were vice versa in castes. Our findings suggest that majority of tribal populations of India carry the protected / less severe allele against VL, while risk / more severe allele for leprosy and Behcet’s disease. This study has potential implications in counseling and management of VL and other infectious diseases.
PMCID: PMC4420251  PMID: 25941808
18.  MTHFR 677C>T Polymorphism and the Risk of Breast Cancer: Evidence from an Original Study and Pooled Data for 28031 Cases and 31880 Controls 
PLoS ONE  2015;10(3):e0120654.
Methylenetetrahydrofolate reductase (MTHFR) acts at an important metabolic point in the regulation of cellular methylation reaction. It assists in the conversion of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. The latter aids in remethylation of homocysteine to de novo methionine that is required for DNA synthesis. The objective of this study was to examine the effect of MTHFR 677 C>T polymorphism on the risk of breast cancer in the Indian sub-continent.
Methods and Results
We genotyped 677 C>T locus in 1096 individuals that were classified into cases (N=588) and controls (N=508). Genotype data were analyzed using chi-square test. No significant difference was observed in the distribution of genotypes between cases and controls in north Indian (P = 0.932), south Indian (P = 0.865), and pooled data (P = 0.680). To develop a consensus regarding the impact of 677C>T polymorphism on breast cancer risk, we also conducted a meta-analysis on 28031 cases and 31880 controls that were pooled from sixty one studies. The overall summary estimate upon meta-analysis suggested no significant correlation between the 677C>T substitution and breast cancer in the dominant model (Fixed effect model: OR = 0.97, P=0.072, Random effects model: OR = 0.96, P = 0.084) or the recessive model (Fixed effect model: OR = 1.05, P = 0.089; Random effects model: OR= 1.08, P= 0.067).
677 C>T substitution does not affect breast cancer risk in the Indo-European and Dravidian populations of India. Analysis on pooled data further ruled out association between the 677 C>T polymorphism and breast cancer. Therefore, 677 C>T substitution does not appear to influence the risk of breast cancer.
PMCID: PMC4372432  PMID: 25803740
19.  Ancient human genomes suggest three ancestral populations for present-day Europeans 
Lazaridis, Iosif | Patterson, Nick | Mittnik, Alissa | Renaud, Gabriel | Mallick, Swapan | Kirsanow, Karola | Sudmant, Peter H. | Schraiber, Joshua G. | Castellano, Sergi | Lipson, Mark | Berger, Bonnie | Economou, Christos | Bollongino, Ruth | Fu, Qiaomei | Bos, Kirsten I. | Nordenfelt, Susanne | Li, Heng | de Filippo, Cesare | Prüfer, Kay | Sawyer, Susanna | Posth, Cosimo | Haak, Wolfgang | Hallgren, Fredrik | Fornander, Elin | Rohland, Nadin | Delsate, Dominique | Francken, Michael | Guinet, Jean-Michel | Wahl, Joachim | Ayodo, George | Babiker, Hamza A. | Bailliet, Graciela | Balanovska, Elena | Balanovsky, Oleg | Barrantes, Ramiro | Bedoya, Gabriel | Ben-Ami, Haim | Bene, Judit | Berrada, Fouad | Bravi, Claudio M. | Brisighelli, Francesca | Busby, George B. J. | Cali, Francesco | Churnosov, Mikhail | Cole, David E. C. | Corach, Daniel | Damba, Larissa | van Driem, George | Dryomov, Stanislav | Dugoujon, Jean-Michel | Fedorova, Sardana A. | Romero, Irene Gallego | Gubina, Marina | Hammer, Michael | Henn, Brenna M. | Hervig, Tor | Hodoglugil, Ugur | Jha, Aashish R. | Karachanak-Yankova, Sena | Khusainova, Rita | Khusnutdinova, Elza | Kittles, Rick | Kivisild, Toomas | Klitz, William | Kučinskas, Vaidutis | Kushniarevich, Alena | Laredj, Leila | Litvinov, Sergey | Loukidis, Theologos | Mahley, Robert W. | Melegh, Béla | Metspalu, Ene | Molina, Julio | Mountain, Joanna | Näkkäläjärvi, Klemetti | Nesheva, Desislava | Nyambo, Thomas | Osipova, Ludmila | Parik, Jüri | Platonov, Fedor | Posukh, Olga | Romano, Valentino | Rothhammer, Francisco | Rudan, Igor | Ruizbakiev, Ruslan | Sahakyan, Hovhannes | Sajantila, Antti | Salas, Antonio | Starikovskaya, Elena B. | Tarekegn, Ayele | Toncheva, Draga | Turdikulova, Shahlo | Uktveryte, Ingrida | Utevska, Olga | Vasquez, René | Villena, Mercedes | Voevoda, Mikhail | Winkler, Cheryl | Yepiskoposyan, Levon | Zalloua, Pierre | Zemunik, Tatijana | Cooper, Alan | Capelli, Cristian | Thomas, Mark G. | Ruiz-Linares, Andres | Tishkoff, Sarah A. | Singh, Lalji | Thangaraj, Kumarasamy | Villems, Richard | Comas, David | Sukernik, Rem | Metspalu, Mait | Meyer, Matthias | Eichler, Evan E. | Burger, Joachim | Slatkin, Montgomery | Pääbo, Svante | Kelso, Janet | Reich, David | Krause, Johannes
Nature  2014;513(7518):409-413.
We sequenced the genomes of a ~7,000 year old farmer from Germany and eight ~8,000 year old hunter-gatherers from Luxembourg and Sweden. We analyzed these and other ancient genomes1–4 with 2,345 contemporary humans to show that most present Europeans derive from at least three highly differentiated populations: West European Hunter-Gatherers (WHG), who contributed ancestry to all Europeans but not to Near Easterners; Ancient North Eurasians (ANE) related to Upper Paleolithic Siberians3, who contributed to both Europeans and Near Easterners; and Early European Farmers (EEF), who were mainly of Near Eastern origin but also harbored WHG-related ancestry. We model these populations’ deep relationships and show that EEF had ~44% ancestry from a “Basal Eurasian” population that split prior to the diversification of other non-African lineages.
PMCID: PMC4170574  PMID: 25230663
20.  c.620C>T mutation in GATA4 is associated with congenital heart disease in South India 
BMC Medical Genetics  2015;16:7.
Congenital heart diseases (CHDs) usually refer to abnormalities in the structure and/or function of the heart that arise before birth. GATA4 plays an important role in embryonic heart development, hence the aim of this study was to find the association of GATA4 mutations with CHD among the south Indian CHD patients.
GATA4 gene was sequenced in 100 CHD patients (ASD, VSD, TOF and SV) and 200 controls. Functional significance of the observed GATA4 mutations was analyzed using PolyPhen, SIFT, PMut, Plink, Haploview, ESE finder 3.0 and CONSITE.
We observed a total of 19 mutations, of which, one was in 5′ UTR, 10 in intronic regions, 3 in coding regions and 5 in 3′ UTR. Of the above mutations, one was associated with Atrial Septal Defect (ASD), two were found to be associated with Tetralogy of Fallot (TOF) and three (rs804280, rs4841587 and rs4841588) were strongly associated with Ventricular Septal Defect (VSD). Interestingly, one promoter mutation (−490 to 100 bp) i.e., 620 C>T (rs61277615, p-value = 0.008514), one splice junction mutation (G>A rs73203482; p-value = 9.6e-3, OR = 6.508) and one intronic mutation rs4841587 (p-value = 4.6e-3, OR = 4.758) were the most significant findings of this study. In silico analysis also proves that some of the mutations reported above are pathogenic.
The present study found that GATA4 genetic variations are associated with ASD, TOF and VSD in South Indian patients. In silico analysis provides further evidence that some of the observed mutations are pathogenic.
Electronic supplementary material
The online version of this article (doi:10.1186/s12881-015-0152-7) contains supplementary material, which is available to authorized users.
PMCID: PMC4422155  PMID: 25928801
Congenital heart disease; GATA4; Mutation; South Indian patients; ASD; TOF; VSD
21.  Mitochondrial disorders: Challenges in diagnosis & treatment 
Mitochondrial dysfunctions are known to be responsible for a number of heterogenous clinical presentations with multi-systemic involvement. Impaired oxidative phosphorylation leading to a decrease in cellular energy (ATP) production is the most important cause underlying these disorders. Despite significant progress made in the field of mitochondrial medicine during the last two decades, the molecular mechanisms underlying these disorders are not fully understood. Since the identification of first mitochondrial DNA (mtDNA) mutation in 1988, there has been an exponential rise in the identification of mtDNA and nuclear DNA mutations that are responsible for mitochondrial dysfunction and disease. Genetic complexity together with ever widening clinical spectrum associated with mitochondrial dysfunction poses a major challenge in diagnosis and treatment. Effective therapy has remained elusive till date and is mostly efficient in relieving symptoms. In this review, we discuss the important clinical and genetic features of mitochondrials disorders with special emphasis on diagnosis and treatment.
PMCID: PMC4405934  PMID: 25857492
Diagnosis; diseases; mitochondrial DNA; mutation; treatment
22.  Association of progesterone receptor gene polymorphism with male infertility and clinical outcome of ICSI 
To investigate the association of Progesterone Receptor (PR) gene variations and male infertility
DNA extraction, PCR and sequencing of PR gene, PROGINS insertion by PCR. Association of the variations with seminal parameters and outcomes of ICSI.
Four known SNPs in the PR gene were identified in the study of which three (rs3740753, rs1042838, rs104283) were co-inherited and in complete linkage disequilibrium with the PROGINS Alu insertion. There were no differences in their frequencies between fertile and infertile males. The rs2020880 was found at a very low frequency only in the controls but not in the infertile subjects. The sperm counts, fertilization rate, embryo quality or pregnancy rates were not different in individuals with or without PROGINS allele.
PR gene alterations are not associated with male infertility or ICSI outcome.
Electronic supplementary material
The online version of this article (doi:10.1007/s10815-013-0074-2) contains supplementary material, which is available to authorized users.
PMCID: PMC3800537  PMID: 23934021
Progesterone receptor; Polymorphism; PROGINS; Male infertility; ICSI; Azoospermia; Sperm counts
23.  Atrial natriuretic peptide gene - a potential biomarker for long QT syndrome 
EXCLI Journal  2014;13:834-842.
This study highlights the possible implication of NPPA (natriuretic peptide precursor A) gene in the etiology of Long QT syndrome (LQTS) by population-based as well as familial study. Three SNPs of NPPA - C-664G, C1363A and T1766C were examined by molecular analyses in LQTS, controls and first degree relatives (FDRs). This study revealed a possible association of 1364 C>A SNP ‘C’ allele with LQTS (p = 0.0013). All three SNPs were in tight linkage disequilibrium. The familial study highlights the association of NPPA SNP with cLQTS and implicating it as a potential biomarker in South Indian population.
PMCID: PMC4464516  PMID: 26417306
atrial natriuretic peptide; long QT syndrome; cardiogenesis; biomarker; polymorphisms
24.  Reduced prevalence of placental malaria in primiparae with blood group O 
Malaria Journal  2014;13:289.
Blood group O protects African children against severe malaria and has reached high prevalence in malarious regions. However, its role in malaria in pregnancy is ambiguous. In 839 delivering Ghanaian women, associations of ABO blood groups with Plasmodium falciparum infection were examined.
Plasmodium falciparum infection was diagnosed in placental blood samples by microscopy and PCR assays. Present or past infection was defined as the detection of parasitaemia or haemozoin by microscopy, or a positive PCR result. Blood groups were inferred from genotyping rs8176719 (indicating the O allele) and rs8176746/rs8176747 (distinguishing the B allele from the A allele).
The majority of women had blood group O (55.4%); present or past P. falciparum infection was seen in 62.3% of all women. Among multiparae, the blood groups had no influence on P. falciparum infection. In contrast, primiparae with blood group O had significantly less present or past infection than women with non-O blood groups (61.5 vs 76.2%, P = 0.007). In multivariate analysis, the odds of present or past placental P. falciparum infection were reduced by 45% in blood group O primiparae (aOR, 0.55 [95% CI, 0.33–0.94]).
The present study shows a clear protective effect of blood group O against malaria in primiparae. This accords with findings in severe malaria and in vitro results. The data underline the relevance of host genetic protection among primiparae, i.e. the high-risk group for malaria in pregnancy, and contribute to the understanding of high O allele frequencies in Africa.
PMCID: PMC4119177  PMID: 25066505
25.  Novel TCAP Mutation c.32C>A Causing Limb Girdle Muscular Dystrophy 2G 
PLoS ONE  2014;9(7):e102763.
TCAP encoded telethonin is a 19 kDa protein, which plays an important role in anchoring titin in Z disc of the sarcomere, and is known to cause LGMD2G, a rare muscle disorder characterised by proximal and distal lower limb weakness, calf hypertrophy and loss of ambulation. A total of 300 individuals with ARLGMD were recruited for this study. Among these we identified 8 clinically well characterised LGMD2G cases from 7 unrelated Dravidian families. Clinical examination revealed predominantly proximo - distal form of weakness, scapular winging, muscle atrophy, calf hypertrophy and foot drop, immunoblot showed either complete absence or severe reduction of telethonin. Genetic analysis revealed a novel nonsense homozygous mutation c.32C>A, p.(Ser11*) in three patients of a consanguineous family and an 8 bp homozygous duplication c.26_33dupAGGTGTCG, p.(Arg12fs31*) in another patient. Both mutations possibly lead to truncated protein or nonsense mediated decay. We could not find any functionally significant TCAP mutation in the remaining 6 samples, except for two other polymorphisms, c.453A>C, p.( = ) and c.-178G>T, which were found in cases and controls. This is the first report from India to demonstrate TCAP association with LGMD2G.
PMCID: PMC4108395  PMID: 25055047

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