What is the significance of mitochondrial DNA in forensic science?

Mitochondrial DNA (mtDNA) is particularly significant in forensic science because it serves as a useful tool in situations where nuclear DNA is either unavailable or has been degraded. Unlike nuclear DNA, which is inherited from both parents and can provide extensive information about an individual's genetic heritage, mtDNA is inherited only from the mother and is present in multiple copies within each cell. This abundance makes it more likely to be recoverable from challenging samples, such as old remains or samples that may have been contaminated or degraded over time.

In forensic investigations, when typical sources of nuclear DNA, such as blood or tissue, cannot be utilized due to degradation or the state of the sample, mtDNA analysis provides a viable alternative. It is especially valuable in cases involving skeletal remains, historical samples, or situations where only small amounts of biological material are available for testing.

This characteristic enhances mtDNA's utility in forensic science, as it allows investigators to potentially identify individuals or establish maternal lineage connections that would otherwise be difficult or impossible to achieve using nuclear DNA, especially in degraded or limited samples.