What is mitochondrial DNA (mt-DNA) inherited from?

Mitochondrial DNA (mt-DNA) is inherited exclusively from the mother. This is because mitochondria, which contain their own DNA, are passed down through the egg cell during reproduction. The sperm contributes nuclear DNA but does not contribute significantly to the mitochondria of the offspring. As a result, every person has mt-DNA that can be traced back through their maternal lineage, which is a key concept used in various fields, including forensic science and genealogy.

In contrast to nuclear DNA, which comes from both parents and combines to create a unique genetic makeup for the child, mitochondrial DNA remains relatively unchanged and is used to study maternal ancestry. This unique inheritance pattern allows scientists to trace genetic lineages and is a valuable tool in forensic investigations for identifying individuals based on their maternal lineage.