One type of DNA used in forensics that is maternally inherited is which of the following?

• A. Nuclear DNA
• B. Viral DNA
• C. Mitochondrial DNA
• D. Bacterial DNA

Answer: (C)

Mitochondrial DNA is inherited from the mother, because the mitochondria in the egg (not the sperm) supply the mtDNA to the embryo. This means everyone in a maternal line shares the same mitochondrial DNA sequence (aside from rare mutations). In forensics, mtDNA is especially useful when the sample is degraded or when only trace, high-copy-number DNA is available, since many mitochondria exist per cell and its sequence can still be analyzed. This makes mtDNA a key tool for linking individuals along maternal lines or for identifying remains when nuclear DNA cannot be recovered, even though it offers less individual discrimination than nuclear DNA. Nuclear DNA comes from both parents, while viral DNA and bacterial DNA are not used to establish maternal inheritance in humans for forensic identification.