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Context: Results from the extensive computation analysis of the 1029 sequenced genomes from India were published in the scientific journal Nucleic Acid Research.

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  • The study was carried out by CSIR constituent labs, CSIR-Institute of Genomics and Integrative Biology (IGIB), Delhi and CSIR-Centre for Cellular and Molecular Biology (CCMB), Hyderabad 
  • The resource can provide useful insights in comprehending genetics at the population and the individual level.

What is a genome?

  • A genome is an organism’s complete set of genetic instructions. 
  • Each genome contains all of the information needed to build that organism and allow it to grow and develop. 
  • Our bodies are made up of millions of cells each with their own complete set of instructions for making us, like a recipe book for the body. This set of instructions is known as our genome and is made up of DNA. 
  • All living things have a unique genome.
  • The human genome is made of 3.2 billion bases of DNA but other organisms have different genome sizes.
  • The instructions in our genome are made up of DNA.
  • Single strands of DNA are coiled up into structures called chromosomes located in the nucleus within each cell.
  • Within our chromosomes, sections of DNA are "read" together to form genes.
  • Genes control different characteristics such as eye colour and height.

Case for an India centric population genomic initiative

  • India has been under-represented in global genome studies.
  • Rich genetic diversity
    • The analysis led to the identification of 55,898,122 single nucleotide variants in the India genome dataset.
    • Unique genomes: 18,016,257 (32.23%) variants were unique and found only in the samples sequenced from India. This emphasizes the need for an India centric population genomic initiative.
    • High population: India is the second largest country in terms of population density with more than 1.3 billion individuals encompassing 17% of the world population. 
  • Further, the population architecture of India has resulted in high prevalence of recessive alleles.
    • Recessive is a quality found in the relationship between two versions of a gene. Individuals receive one version of a gene, called an allele, from each parent. 
    • If the alleles are different, the dominant allele will be expressed, while the effect of the other allele, called recessive, is masked.

IndiGen Program

  • CSIR initiated the IndiGen Program in April 2019. 
  • Under this program, the whole genome sequencing of 1029 self-declared healthy Indians drawn from across the country has been completed. 
  • It has an objective to classify variants involved in mendelian disorders and improve precision medicine outcomes.
  • The resource can also enable the 
    • Identification of markers for carrier screening, 
    • Variations causing genetic diseases, 
    • Prevention of adverse events and 
    • Provide better diagnosis and optimal therapy through mining data of clinically actionable pharmacogenetic variants. 
  • Significance:
    • The phased data will allow researchers to build Indian-specific reference genome dataset and efficiently impute haplotype information. 
    • It will augment capability in genomics and understanding of India’s genomic diversity strengthening the country’s response to the current and future pandemics.