A decomposed body is recovered from a river after 3 months. Nuclear DNA is severely degraded. The most appropriate DNA source for identification in this scenario is:
- A Mitochondrial DNA from hair shaft (anagen root absent) ✓
- B Nuclear DNA from skin cells
- C Y-chromosome STR from dental pulp
- D Autosomal STR from bone marrow
Correct answer: A. Mitochondrial DNA from hair shaft (anagen root absent)
Explanation
Mitochondrial DNA (mtDNA) is present in hundreds to thousands of copies per cell (vs. two copies of nuclear DNA), making it far more resistant to degradation. Hair shafts without roots lack nuclear DNA but contain mtDNA in the cortex. mtDNA analysis is the method of choice for shed hairs, old skeletal remains, and highly degraded samples. Dental pulp contains nuclear DNA but is harder to access in advanced decomposition.
Reference: The Essentials of Forensic Medicine and Toxicology (Narayan Reddy), 34th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.