Interviewee: Matt Ridley.
Every human cell has a "second" genome, found in the cell's energy-generating organelle, the mitochondrion. Comparison of control region sequences of mt DNA reveals that most people have a unique pattern of single nucleotide polymorphisms (SNPs). These sequence differences, in turn, are the basis for far-ranging investigations on human DNA diversity and the evolution of hominids.
(DNAi Location: Genome > Tour > Genome spots > mt: Genealogy)
Transcript:
There's one set of human genes that's not found in the nucleus. It's in the mitochondrion. The mitochondrion is a sort of power pack inside the cell."+" Mitochondrial genes are passed through the mother's line, so I would get mine from my mother, and my son would get his from my wife. Because they don't mix with genes from the father's line, mitochondrial genes can be used to trace a sort of lineage right the way back to when our first ancestors came out of Africa.
DNA found in the mitochondrion of a cell differs in structure and is separate from the DNA found in the cell nucleus. Mitochondrial DNA, or mtDNA, exists as a circular loop of double-stranded DNA rather than the linear form found in nuclear DNA. However,
This illustration shows the two major mitochondrial DNA lineages. The lower branch includes only African populations. The upper branch has both African and non-African members.