Heteroplasmy - GS questions based on daily current affairs

1)   What is Heteroplasmy?

a. Having the male and female different in a species
b. Presence of more than one type of mitochondrial DNA within a cell or individual
c. Having twins of different sexes
d. None of the above
Answer  Explanation 

ANSWER: Presence of more than one type of mitochondrial DNA within a cell or individual

Explanation:

  • Mitochondria, the powerhouses of the cell, are unique in several ways.
  • A cell can have multiple mitochondriae, with each mitochondriae differing from one another by a few variations. This phenomenon is known as heteroplasmy.
  • Heteroplasmy can vary between cells of the same tissue, organ, individual or even between individuals of the same family. It is present in healthy individuals too.
  • A person does not manifest the disease when the heteroplasmy frequencies are low, usually less than 10 per cent.
  • Institute of Genomics and Integrative Biology (IGIB), Delhi, has the global data of every disease causing mitochondrial mutation and its frequency.