BBC - Surnames, Genes and Genealogy

Surnames, Genes and Genealogy

DNA

Within our DNA we all carry a message from our ancestors in every cell of our body. Bryan Sykes, Professor of Human Genetics at Oxford University, claims that almost all contemporary Europeans are the direct descendants of just seven women, who lived at different times over the last 45,000 years. These 'Seven Daughters of Eve' have been identified by his work on mitochondrial DNA, which is passed from mothers to daughters.

Bryan Sykes has now turned his attention to the Y chromosome that is passed from fathers to sons with little or no change over the generations. Tens of thousands of different Y chromosomes have evolved over millions of years, so that each male line has its own identifiable genetic 'fingerprint'. As surnames too are inherited through the male line, all men with the same surname may also share the same DNA on the Y chromosome. This will be true only where a surname has a single-family origin back in the Middle Ages, and where there has been no illegitimacy or the adoption of the surname by stepchildren.

The theory is tested by taking cheek cell samples from men sharing the same surname and from others in random control groups. The procedure is painless and easy. The huge advances that have been made in understanding how genetic directions are transmitted from one generation to the next is enabling scientists to identify the distinctive patterns that are passed down in the male line of each family.

The DNA tests give strong support to the idea that many of our surnames have single-family origins, and with commoner names they can point to close relationships that might otherwise be difficult to prove. This new type of information is welcomed by historians who have argued that many surnames have just one source but who have not usually been able to prove their arguments because of inadequate historical records. But a few reservations are expressed. People with the same name who were not as prolific might get overlooked, and could it be that in some cases the progenitor of a distinctive DNA pattern was himself illegitimate and not the true originator of the surname? DNA testing is a major new tool for family historians, but it has to be examined just as critically as the traditional historical sources.