Genome represents the complete hereditary information of an organism encoded in its DNA. Genome comprises both the genes and the non-coding sequences of the DNA. It covers the entire gamut of building, running, maintaining an organism and passing life on to next generation. The word Genome was coined for the first time by Hans Winkler. He was working as a professor of Botany at the University of Hamburg in Germany.
Aspirants would find this topic very helpful in the IAS Exam.
What is a Genome Made of?
In almost all living things on earth, genome is made of a chemical called DNA. The Genome contains genes which affect the characteristics of the living organism. Genome contains chromosome, these chromosomes contain genes, and these genes are made up of DNA. All living things are made of different unique genomes. Humans, animals, birds, all have different genomes, and no two humans have the same genome. The difference in the genome between 2 people is smaller than the genome difference between a human and a chimpanzee.
How Many Genomes do Humans have?
Human genome comprises of 23 chromosome pairs with a total of 3 billion DNA base pairs. There are 24 different types of human chromosomes, out of these 22 are autosomal chromosomes in addition there are X and Y Chromosomes that determines the sex. The number of human protein-coding genes are estimated to be in the range of 20,000 – 25,000. As the genome sequencing quality and gene finding methodologies have kept improving over time, the estimated number of genes in human body has been steadily decreasing from initial predictions of 1,00,000 and above.
What is DNA?
DNA stands for Deoxyribonucleic acid (DNA). It is a molecule which is made up of biological instructions which result in the uniqueness of each species. DNA is passed from adult organisms to their offspring at the time of reproduction.
Genome – Latest Updates
- As per the research carried out by the Council for Scientific and Industrial Research (CSIR)-Institute of Genomics and Integrative Biology, Delhi and CSIR-Centre for Cellular and Molecular Biology, Hyderabad, thirty-two percent of genetic variations in Indian genome sequences are unique as compared to global genomes. Results from the extensive computation analysis of 1,029 sequenced genomes from India were published recently in the journal Nucleic Acid Research.
- A new study published in Nature, conducted through Human Heredity and Health in Africa (H3Africa), a consortium devoted to increasing African representation in genetics research, uncovered 3 million new genetic variants in one of the most extensive studies of African genomes reported to date. The research team performed whole-genome sequencing analyses of 426 individuals that represent 50 ethnolinguistic groups, including previously unsampled populations, to explore the breadth of genomic diversity across Africa.
The above details would help candidates preparing for UPSC 2021.