Few clues about African ancestry to be found in mitochondrial DNA

A study published today in the open access journal BMC Biology reveals that fewer than 10% of African American mitochondrial DNA sequences analysed can be matched to mitochondrial DNA from one single African ethnic group. There has been a growing interest in the use of mitochondrial DNA to trace maternal ancestries, and several companies now offer to analyse individuals’ mitochondrial DNA sequences to obtain information about their origins. The current study suggests that only one in nine African Americans may be able to find clues about where their ancestors came from, in their mitochondrial DNA.

Bert Ely, from the University of North Carolina, and colleagues from other Universities in the USA analysed a database of the human variable region, or HVS-1 region, of mitochondrial (mt) DNA sequences from sub-Saharan Africa. They then compared two samples of African American mt DNA sequences to the database, to identify exact matches to the sub-Saharan sequences.

Ely et al.’s results show that more than half of the African American HSV-1 sequences were found in many different sub-Saharan ethnic groups. Forty percent of the African American HSV-1 sequences did not match any sequences in the database and fewer than 10% were an exact match to a sequence from a single African ethnic group.