Sheikh Nizamuddin

Genome-wide analysis correlates Ayurveda Prakriti

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.

Dissecting the influence of Neolithic demic diffusion on Indian Y-chromosome pool through J2-M172 haplogroup

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.

A novel gene THSD7A is associated with obesity.

Body mass index (BMI) is a non-invasive measurement of obesity. It is commonly used for assessing adiposity and obesity-related risk prediction. Genetic differences between ethnic groups are important factors, which contribute to the variation in phenotypic effects. India inhabited by the first out-of-Africa human population and the contemporary Indian populations are admixture of two ancestral populations; ancestral north Indians (ANI) and ancestral south Indians (ASI). Although ANI are related to Europeans, ASI are not related to any group outside Indian-subcontinent. Hence, we expect novel genetic loci associated with BMI. In association analysis, we found eight genic SNPs in extreme of distribution (P⩽3.75 × 10−5), of which WWOX has already been reported to be associated with obesity-related traits hence excluded from further study. Interestingly, we observed rs1526538, an intronic SNP of THSD7A; a novel gene significantly associated with obesity (P=2.88 × 10−5, 8.922 × 10−6 and 2.504 × 10−9 in discovery, replication and combined stages, respectively). THSD7A is neural N-glycoprotein, which promotes angiogenesis and it is well known that angiogenesis modulates obesity, adipose metabolism and insulin sensitivity, hence our result find a correlation. This information can be used for drug target, early diagnosis of obesity and treatment.

c.*84G>A Mutation in CETP Is Associated with Coronary Artery Disease in South Indians

Background 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. Methods 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. Conclusions 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.

IL10 Variant g.5311A Is Associated with Visceral Leishmaniasis in Indian Population.

Background 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. Methodology 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.

Association between Myocardial Infarction and Dermatoglyphics: A Cross-Sectional Study

Background: Myocardial infarction (MI) is a multifactorial and polygenic cardiovascular disease with high mortality rate. Early diagnosis could help in precautionary measures and change in life style. Many studies used dermatoglyphics as noninvasive technique to predict the incidence of genetic diseases. Here, we tried to assess the association of dermatoglyphic pattern between MI and controls. Methods: We investigated dermatoglyphic patterns among 800 participants (n=400 MI cases and n=400 control groups) representing South Indian population. Patients with MI were compared with control groups who did not have any history of MI. Results: Showed higher frequency whorls in MI patients and loops in control group (p<0.001). The study showed significant difference in distribution of whorl (OR = 0.298, 95%CI=0.2230.399, p=0.0001), loop (OR = 3.537, 95%CI=2.639-4.741, p=0.0001), arch (OR = 0.545, 95%CI=0.405-0.733, p=0.0001). Further, mean values of A-B ridge count (OR = 1.421, 95%CI=1.167-1.731, P=0.0001) of MI and control groups were significant (p<0.05). Conclusion: The present study showed that there is an association between dermatoglyphic patterns and MI cases. Further, findings suggest that dermatoglyphic patterns may contribute to etiology of early prediction of MI.

TG haplotype in the LRP8 is associated with myocardial infarction in south Indian population

Myocardial infarction (MI) is a complex multifactorial cardiovascular disease. India experiences a much greater burden of MI, also suggesting an experimental increase of this burden in the future. The absolute reasons for MI are context dependent and differ with different geographical settings. Several reports indicate that SNPs that are associated with certain diseases in other populations may not be associated with Indian population. It is, therefore, important to validate the association of SNPs. Low density lipoprotein receptor related protein 8 (LRP8) gene plays central role in human lipoprotein metabolism as it facilitates the clearance of bad cholesterol LDL, VLDL from plasma and is reported to be associated with MI in the western population. However, this gene has not been studied in the South Indian population. We aim to test the role of the LRP8 gene variants correlating with the lipid profile in MI patients in South Indian population. We sequenced regions of SNPs rs10788952, rs7546246, rs2297660 and rs5174 of LRP8 in 100 MI patients and 100 age-matched controls. Our result revealed a total of 4 variations. None of the SNPs were significantly associated with MI (p>0.973). Interestingly, haplotype based association analysis showed TG and CG of rs10788952 and rs7546246 significantly associated with MI (p<0.01 and p<0.00005) and in particular, haplotype TG was positively correlated with the risk of MI, as this increased the LDL and total cholesterol level in MI patients in south Indians. Our results suggest that haplotype TG is a risk factor for MI in South Indian population.

Signatures of natural selection in the drug metabolizing enzyme genes: Opportunity for developing personalized and precision medicine

Modern human experienced various selective pressures; including range of xenobiotics which contributed to heterogeneity of drug response. Many genes involve in pharmacokinetics and dynamics of drug, have been reported under natural selection. However, none of the studies have utilized comprehensive information of drug-centered PharmGKB pathways. We have extended this work and aimed to investigate sweep signals, using 1,798 subjects, from 53 Indian and 15 other world populations. We observed that modifiers which alters the biochemical function of other genes, have excess of natural selection (median std-z score=0.033±0.95; p-value=1.7×10−9-3.7×10−3). Taxane and statin primarily used for chemotherapy and lowering cholesterol level, respectively; and well known for heterogeneous drug response. We observed that pharmacokinetic pathway of taxane and statins are under natural selection (p-value=2.53×10−9and 2.73×10−9-1.09×10−4; q-value=1.28×10−7 and 6.91×10−6-1.1×10−3). We also observed signal of selection in Ibuprofen pharmacokinetics (p-value=1.76×10−5; q-value =2.22×10−4), beta-agonist/beta-blocker pharmacodynamics (p-value=4.79×10−4; q-value =4.04×10−4) and Zidovudin pharmacokinetics/dynamic pathway (p-value=7.0×10−4; q-value =5.06×10−4). Hard sweeps signals were observed in a total of 322 loci. Of which, 53 affect mRNA expression (p-value<0.001) and 16 were already reported with therapeutic response. Interestingly, we observed that Africans have experience 2 phases of natural selection, one at ~30,000 another at ~10,000 years before present.

Genetic polymorphism of Cytochrome-P450-2C9 (CYP2C9) in Indian populations

Cytochrome-P450-2C9 (CYP2C9) metabolizes wide range of drugs and highly express in human liver. Various mutations of CYP2C9 (R144C, I359L etc.), associated with drug-response, are highly diverse. We aimed to investigate the genetic diversity of CYP2C9 in Indian-subcontinent, using 1278 subjects from 36 populations. High frequency of CYP2C9*3 (0-0.179) was observed, comparative to other populations, including Europeans. Subjects having CYP2C9*3/*3 requires lower dose of warfarin, comparative to CYP2C9*1/*3 or CYP2C9*1/*1. Since, Indians are practicing marriage among their caste system, we predicted and observed high frequency (0-0.05) of CYP2C9*3/*3. Out of 21 populations, living outside of Indian subcontinent, only Toscani and Southern Han-Chinese have 0.009 and 0.01 CYP2C9*3/*3, respectively, lower than Indians,. We found a non-synonymous mutation (L362V), observed only in Indian-subcontinent, and have 0-0.056 allelic, 0-0.037 L/V and 00.037 V/V genotype frequency. We observed unfavorable interatomic interactions between hydroxylation sites of warfarin and reactive oxyferryl heme in mutant, comparative to wild-type CYP2C9, in molecular dynamic simulations; and predict lower kinetic activity.

Epigenetic signatures of high altitude adaptation in Tibetan population

Genetic adaptations in high-altitude populations which provide them survival benefit/advantage in high altitude have been well documented. However, till date, very limited studies on the epigenetic adaptation in high altitude human population. Therefore, we aimed to study the high altitude adaptation in Tibetan population, with respect to epigenetic adaptation. DNA methylation is one of the major epigenetic marks, role of which has been suspected in a spectrum of gene-environment interaction and biological processes. The most common form of DNA methylation in vertebrates is 5-methylcytosine, mostly observed in CpG rich promoter region. Recent advancements in the field of DNA sequencing made it possible to analyse genome-wide methylation rapidly with high resolution, however, study of methylation at population level to explore population specific geneenvironment interaction is not in long race. Therefore, the present study has been designed to analyse DNA methylation signatures (using whole genome bisulfite sequencing) in Tibetan population (presently inhabiting Karnataka since last 50-60 years) but were native of Ladakh (above 5000 meters) since generations along with Indian populations who are living at low altitude (~10 meters). DNA was isolated from blood, collected from the subjects after informed consent. DNA was converted using bisulfite reagents and whole genome bisulfite sequencing (WGBS) was performed using Illumina-2500 platform (Medgenome Pvt. Ltd.). Analysis of WGBS data was performed using various statistical/bioinformatics tools such as bedtools, Bioconductor and R package to find out methylation sites that are significantly different. We observed 6 differentially methylated regions in Tibetans, highland population, of which, 5 were hypo methylated and one was hypermethylated. The present study reveals differential hypo methylation of CYP2E1 and CRELD1 genes, previously reported to be involved in high altitude adaptation (Simonson et al., 2010; Dong et al., 2014), which would of greater interest. Besides this, we observed novel epigenetic differences in chromosome 7, 11 and 15. Our study, for the first time reveals genome wide level of methylation difference in Tibetan population (native of high altitude since generations) residing in low altitude with other mainland Indians of low altitude which could be important epigenetic markers of natural selection. Comparison with native high altitude Tibetan would make the scenario clearer, which is in the process. Citation: Basak, N., Nizamuddin, S. and Thangaraj, K. Epigenetic signatures of high altitude adaptation in Tibetan population [Abstract]. In: Abstracts of the NGBT conference; Oct 02-04, 2017; Bhubaneswar, Odisha, India: Can J biotech, Volume 1, Special Issue, Page 113. https://doi.org/10.24870/cjb.2017-a99