Question

Satellite DNA is useful tool in

• A. Forensic science
• B. Genetic engineering
• C. Organ transplantation
• D. Sex determination

Answer 1

The correct option is A Forensic science

About 3% or so of the human genome has highly repetitive sequences or simple-sequence DNA or simple sequence repeats or satellite DNA. It does not encode proteins or RNAs but have identifiable functional importance owing to their presence in centromeres and telomeres; which makes option B wrong as genetic engineering mainly aims at transfer of genes producing desired products. Satellite DNA show relative uniformity within species and great variability between closely related species. This DNA polymorphism is revealed during DNA finger printing in identification of suspect. For the purpose, restriction enzyme digested DNA samples are sorted by gel electrophoresis followed by southern blotting. Finally, radioactive probes are washed over the nylon surface to allow their joining to any DNA fragments of same composition. Correct option is A. Sex determination in human is governed by presence or absence of Y-chromosome, not by satellite DNA which makes option D wrong. Organ transplantation mainly aims at immune system; option C is wrong.

So, the correct answer is 'Forensic science'