Luke... I might not actually be your father.

Oops:

Imagine receiving the results of a genetic test that suggests that your son is not your son. Was there a mix-up in the maternity ward?

Fortunately, in this case it was a slip-up in the genetics lab contracted by personal genomics company 23andMe to process its customers' samples. But the news that the Californian firm has supplied 96 people with someone else's results will add to the pressure for more regulation of this emerging industry.

When privacy advocates argue that non-felons' DNA should be kept out of government databases, this is one of the crucial reasons why. You can't simply regulate away errors, human or silicon.