Genetic Screening

Why in the news

• Athletes across the world are resorting to genetic screening for better performance and are trying to improve their performance with the help of supplements by checking for food allergies and deficiencies of essential minerals and vitamins in their bodies.
• In 2017, the Board of Control for Cricket in India (BCCI) reportedly introduced genetic screening to help Indian male cricketers increase speed, reduce fat, improve recovery time and build muscle.

What is genetic screening

• Genetic screening or genetic testing was started to detect diseases or tendencies.
  • Its use in sports began in the late 1990s, when scientists began to accumulate evidence of the role of genes in influencing various aspects of athletic performance.
• Genetic testing involves decoding the instructions stored in the deoxyribonucleic acid (DNA) present in cells.
  • The code in DNA determines everything from how the body works to its appearance.
  • It also affects your chances of developing certain diseases.
• It is stored in genetic data as specific sequences of four letters or chemicals (nitrogen bases) - adenine, guanine, cytosine and thymine.
  • These sequences are read by cellular machinery, which builds amino acids to supply the body with proteins.
• Scientists identify mutations that contribute to unique athletic characteristics and traits by studying genetic variants that arise from mutations in specific DNA sequences.
  • Ultimately, such mutations are introduced into athletes in an attempt to improve their performance.

Example

• Finnish skiing athlete Eero Antero Mäntyranta had a red blood cell count 20 percent higher than other athletes, despite all the other athletes training the same as him.
  • In the 1990s, scientists identified a rare mutation in a gene in 50 of the 200 members of his family, including the athlete, that increased the oxygen-carrying capacity of their red blood cells by 25–50 percent and enhanced their performance.
  • The athlete won seven medals in four Olympic Games in the 1960s.

De-coding the DNA

• As part of the Human Genome Project, launched in October 1990, the initial sequencing of the human genome was announced in the year 2000.
  • Having this information publicly available helped scientists around the world to understand the mysteries of human biology.
• In 1998, scientists first identified the angiotensin-converting enzyme (ACE) gene, involved in the control of blood pressure and skeletal muscle function.
  • One variant of this gene, ACE-I, is associated with endurance performance, giving runners, sailors, and mountain climbers an edge over others.
  • Another variant of this gene, ACE-D, is associated with increased strength, which is essential for weight lifting.
• Similarly, the gene alpha-actinin 3 (ACTN3) is also involved in improving athletic performance.
  • This gene produces the ACTN3 protein, which is found in skeletal muscle tissue, specifically in type 2 or “fast-twitch” muscle fibers.
  • These muscle fibers are known to produce short, powerful movements.
• Genetic testing can also detect lactose intolerance.
  • These tests can also identify specific food allergies and help make dietary adjustments to improve performance.