Why in news?

• Recently, the Department of Biotechnology (DBT) said that the exercise to sequence 10,000 Indian human genomes is about two-thirds complete.
  • About 7,000 Indian genomes have already been sequenced of which, 3,000 are available for public access by researchers.
• This exercise is being conducted to create a database under the Centre-backed Genome India Project.

What’s in today’s article?

• Genome sequencing
• Genome India Project

What is genome sequencing?

• Human genome
  • The human genome is the entire set of deoxyribonucleic acid (DNA) residing in the nucleus of every cell of each human body.
  • It carries the complete genetic information responsible for the development and functioning of the organism.
  • The DNA consists of a double-stranded molecule built up by four bases – adenine (A), cytosine (C), guanine (G) and thymine (T).
  • Every base on one strand pairs with a complementary base on the other strand (A with T and C with G).
  • In all, the genome is made up of approximately 3.05 billion such base pairs.
• Genome sequencing
  • While the sequence or order of base pairs is identical in all humans, compared to another species, there are differences in the genome of every human being that makes them unique.
  • The process of deciphering the order of base pairs, to decode the genetic fingerprint of a human is called genome sequencing.
  • In other words, Genome sequencing is the process of determining the complete DNA sequence of an organism's genome.
  • There are several methods of genome sequencing, but the most common is called next-generation sequencing (NGS).
  • NGS allows for rapid, accurate, and cost-effective sequencing of large amounts of DNA.
• Human Genome Project (HGP)
  • In 1990, a group of scientists began to work on determining the whole sequence of the human genome under the Human Genome Project.
  • The project released the latest version of the complete human genome in 2023, with a 0.3% error margin.
  • The process of whole-genome sequencing, made possible by the Human Genome Project, now facilitates the reading of a person’s individual genome to identify differences from the average human genome.
  • These differences or mutations can tell us about each human’s susceptibility or future vulnerability to a disease, their reaction or sensitivity to a particular stimulus, and so on.

What are the applications of genome sequencing?

• To evaluate rare disorder
  • Genome sequencing has been used to evaluate rare disorders, preconditions for disorders, even cancer from the viewpoint of genetics, rather than as diseases of certain organs.
  • Nearly 10,000 diseases — including cystic fibrosis and thalassemia — are known to be the result of a single gene malfunctioning.
• Tool for prenatal screening
  • It has also been used as a tool for prenatal screening, to investigate whether the foetus has genetic disorders or anomalies.
  • Technology Crispr, which relies on sequencing, may potentially allow scientists to repair disease-causing mutations in human genomes.
• In public health
  • Sequencing has been used to read the codes of viruses.
  • One of its first practical usages was in 2014, when a group of scientists sequenced samples of Ebola from infected African patients to show how genomic data of viruses could reveal hidden pathways of transmission.
  • In January 2020, at the start of the Covid-19 pandemic, Chinese scientist sequenced the genome of a novel pathogen.
    • Later, genome sequencing of the virus led to the development of vaccine and the creation of diagnostic PCR machines.
    • To enable an effective COVID-19 pandemic response, researchers kept track of emerging variants and conducting further studies about their transmissibility, immune escape and potential to cause severe disease.
    • Genomic sequencing became one of the first steps in this important process.
  • India also put in place a sequencing framework. The Indian SARS-COV-2 Genomics Consortia (INSACOG) was tasked with scanning coronavirus samples from patients.
• Uses at the population level
  • Advanced analytics and AI could be applied to essential datasets created by collecting genomic profiles across the population.
  • This would allow to develop greater understanding of causative factors and potential treatments of diseases.

What is Genome India project?

• The Genome India Project is a gene mapping project sanctioned by the Department of Biotechnology.
• It was launched with the goal of creating a comprehensive database of genetic variations among the Indian population.
• The project aims to sequence the genomes of over 10,000 Indians from different regions of the country and establish a reference genome for the Indian population.

What is the significance of the Genome India project?

• To learn about genetic variants unique to the Indian population
  • This project allows researchers to learn about genetic variants unique to India’s population groups and use that to customise drugs and therapies.
  • This will help unravel the genetic underpinnings of chronic diseases currently on the rise in India, for example, diabetes, hypertension, cardiovascular diseases, neurodegenerative disorders, and cancer.
• Database for 1.3 billion population
  • India’s 1.3 billion-strong population consists of over 4,600 population groups, many of which are endogamous.
  • Thus, the Indian population harbours distinct variations, with disease-causing mutations often amplified within some of these groups.
  • Findings from population-based or disease-based human genetics research from other populations of the world cannot be extrapolated to Indians.