Genetic variations in indian population implication for health

Abstract

In past, our knowledge about human genetic variation was limited to mainly the rare changes newlinein the number and structure of chromosomes which included aneuploidies, heteromorphisms, newlinerearrangements and other polymorphism, large enough to be visualized by microscopic newlinetechniques. With the advances in molecular biology came the single nucleotide polymorphism newline(SNPs) in DNA, which is the most prevalent type of genetic variation and identified mainly newlineusing PCR-based methods. Recently, copy number variants (CNVs) are highlighted to be a newlinesignificant source of human genetic variation accounting for disease susceptibility and disease newlinedevelopment, thus revealing the gap between long-recognized microscopic chromosomal newlinealterations and invisible changes at nucleotide level. newlineCopy number variation (CNV) can be defined as segments of DNA ranging in size from newlinekilobases (larger than 1 kb) to several megabases (Mb) varying in copy number in comparison newlineto the reference genome. Deletions, duplications, segmental duplication, insertions, and newlinetranslocations all result in CNVs. Rapid advances in the technologies have enabled the newlinedetection of CNVs on larger scale. Thus, depending on the method of detection, it has been newlineestimated that CNVs may cover about 12% of the human genes. The discovery of submicroscopic copy-number variations (CNVs) present in human genome newlinehas dramatically changed our perspective on DNA structural variation and development of newlinedisease. Advancement in technology has allowed for the analysis of CNVs in thousands of newlineindividuals with or without a specific disease. Till date many researchers have addressed the newlinepresence of CNVs in the human genome and their association with common human diseases newlineincluding neuropsychiatric, autoimmune, infectious, and many more, whereas others found newlineevidence that CNVs are not associated with common diseases. newline