Africans in Yorkshire? the deepest-rooting clade of the Y phylogeny within an English genealogy

The presence of Africans in Britain has been recorded since Roman times, but has left no apparent genetic trace among modern inhabitants. Y chromosomes belonging to the deepest-rooting clade of the Y phylogeny, haplogroup A, are regarded as African-specific, and no examples have been reported from Britain or elsewhere in western Europe. We describe the presence of a haplogroup A1 chromosome in an indigenous British male; comparison with African examples suggests a western African origin. Seven out of eighteen men carrying the same rare east-Yorkshire surname as the original male also carry haplogroup A1 chromosomes, and documentary research resolves them into two genealogies with most-recent-common-ancestors living in Yorkshire in the late eighteenth century. Analysis using 77 Y-STRs (short tandem repeats) is consistent with coalescence a few generations earlier. Our findings represent the first genetic evidence of Africans among ‘indigenous’ British, and emphasise the complexity of human migration history, as well as the pitfalls of assigning geographical origin from Y-chromosomal haplotypes