Post by annienormanna on Jan 24, 2007 12:36:02 GMT -5
news.bbc.co.uk/2/hi/science/nature/6293333.stm
People of African origin have lived in Britain for centuries, according to genetic evidence.
A Leicester University study found that seven men with a rare Yorkshire surname carry a genetic signature previously found only in people of African origin.
The men seem to have shared a common ancestor in the 18th Century, but the African DNA lineage they carry may have reached Britain centuries earlier.
Details of the study appear in the European Journal of Human Genetics.
The scientists declined to disclose the men's surname in order to protect their anonymity.
The discovery came out of genetic work looking at the relationship between the male, or Y, chromosome and surnames.
The Y chromosome is a package of genetic material normally found only in males.
It is passed down from father to son, more or less unchanged, just like a surname.
Rare lineage
But over time, the Y chromosome accumulates small changes in its DNA sequence, allowing scientists to study the relationships between different male lineages.
Y chromosomes can be classified into different groups (called haplogroups) which, to some extent, reflect a person's geographical ancestry.
Certain haplogroups might be very common in, for example, East Asia and very rare in Europe.
By chance, the researchers discovered a white man with a rare Yorkshire surname carrying a Y chromosome haplogroup that had previously been found only in West African men. And even there, it is relatively uncommon.
"We found that he was in haplogroup A1, which is highly West African-specific," said Turi King, a co-author on the study at the University of Leicester.
"It is incredibly rare, there are only 25 other people known worldwide and they are all African."
People of African origin have lived in Britain for centuries, according to genetic evidence.
A Leicester University study found that seven men with a rare Yorkshire surname carry a genetic signature previously found only in people of African origin.
The men seem to have shared a common ancestor in the 18th Century, but the African DNA lineage they carry may have reached Britain centuries earlier.
Details of the study appear in the European Journal of Human Genetics.
The scientists declined to disclose the men's surname in order to protect their anonymity.
The discovery came out of genetic work looking at the relationship between the male, or Y, chromosome and surnames.
The Y chromosome is a package of genetic material normally found only in males.
It is passed down from father to son, more or less unchanged, just like a surname.
Rare lineage
But over time, the Y chromosome accumulates small changes in its DNA sequence, allowing scientists to study the relationships between different male lineages.
Y chromosomes can be classified into different groups (called haplogroups) which, to some extent, reflect a person's geographical ancestry.
Certain haplogroups might be very common in, for example, East Asia and very rare in Europe.
By chance, the researchers discovered a white man with a rare Yorkshire surname carrying a Y chromosome haplogroup that had previously been found only in West African men. And even there, it is relatively uncommon.
"We found that he was in haplogroup A1, which is highly West African-specific," said Turi King, a co-author on the study at the University of Leicester.
"It is incredibly rare, there are only 25 other people known worldwide and they are all African."
