By Shuchi Giridhar
Bethesda, Maryland, Aug 1: A genome is an organism’s complete set of genetic information. Human beings have 23 pairs of chromosomes stored in the nucleus of every cell in their bodies. The chromosomes are lengthy threads or strands of Deoxyribo Nucleic Acid (DNA) molecules that stay securely coiled in a cell’s nucleus. Human chromosomes contain around 3 billion DNA molecules. There are only four types of DNA molecules: A for Adenine, T for Thiamine, G for Guanine, and C for Cytosine.
A gene is a basic unit of heredity composed of a sequence of DNA molecules (one copy inherited from each parent) and are located on chromosomes. Each gene has a specific purpose. It specifies the steps that must be taken in order for a gene product, such as RNA, protein, or enzyme, to be produced in the cell. Proteins are the building components for everything in your body, including bones and teeth, hair and earlobes, muscles, and blood.
Enzymes are proteins that aid in the catalysis of several metabolic reactions in the body. Because genes affect both
structure and function, they determine an organism’s traits (characteristics), such as fur colour in dogs, eye and hair colour in humans, and so on. Scientists now believe that each gene in the body can produce up to ten distinct proteins. That’s over 300,000 proteins derived from only 250,000 to 30,000 genes! The rest of the DNA either helps to regulate gene function or has no purpose and is referred to as Junk DNA.
Human Genome Data
When researchers released the first version of the human genome sequence in 2001, it was a landmark moment in the history of life sciences. However, because it was a draft (preliminary) version, it was not complete, with 15% of the genome still to be deciphered. To comprehend, consider the following analogy. Consider a 100-page book that is missing 15 pages. One can get a good understanding from the book but lose out on many details, some of which may be critical for understanding the plot. And when we talk about the human genome, which has more than three billion DNA base pairs, we’re talking about missing out four hundred fifty million missing base pairs.
Why has it taken so long to decipher the human genome?
These 15% of the genome were the most difficult regions of the genome, necessitating additional research and technical innovation in order to be deciphered. Researchers ultimately put it all together in 2021, twenty-one years later. This fills in the gaps in the previous versions’ long list of errors while adding critical new information. To solve these gaps, a team of over 99 academic groups from 30 institutions organised a worldwide partnership known as the Telomere-to-Telomere (T2T) Consortium. This will lead to a deeper understanding of how the human body functions in
both normal and pathological states, which will aid in the development of treatments and medicines.