Men who delve into their family history by having their DNA analyzed may find more information than they expected. They may find out that they are infertile.
According to NewScientist.com, many companies offering genealogical testing screen male customers' DNA for a region of the Y chromosome called DYS464 that happens to be linked with infertility. If it is missing, it's odds-on that the customer is infertile.
Companies should either stop looking at DYS464 or warn customers beforehand that it could reveal infertility, says Mark Jobling of the University of Leicester, UK. "I think it's daft to type DYS464," he says. "People are buying a genealogy test but end up getting a fertility test." A study by Jobling's team suggests that 1 in 1000 men has the deletion (Journal of Medical Genetics, vol. 42, p 366).
A man may believe that he is the father of his children, only to find out after a genetic test the unwelcome information that he is unlikely to be the biological father.