A study published today in Current Biology compares the DNA of 150 randomly chosen men who share British surnames, and finds that some of them are actually related.
We show that sharing a surname significantly elevates the probability of sharing a Y-chromosomal haplotype and that this probability increases as surname frequency decreases. [Link]It's long been a rule of thumb among genealogists that the rarer a surname is within a limited geographical region, the more likely it is that two people sharing the surname are related. The study showed that there was "no link for Smith, Jones, and Taylor, but a clear link for Attenborough, Widdowson, and Grewcock."
The study summary does raise some interesting possibilities for new CSI episodes.
Within our sample, we estimate that up to 24% of pairs share recent ancestry and that a large surname-based forensic database might contribute to the intelligence-led investigation of up to ~70 rapes and murders per year in the UK.In a column today at Nature.com, researcher Mark Jobling admits that some of the results were obvious, but that the degree of correlation between genetics and surnames has never been established, and that he could have gone even further.
Interestingly, a search of the UK electoral register turns up some 61 entries for the surname Bastard.
Jobling says that he toyed with the idea of investigating this group to see if their degree of relatedness is lower. But in the end, he says, he tactfully demurred. "We were worried that people would think we were taking the piss." [Link]