by The Urban Blabbermouth
There you are, a professional criminal, and you go to all the trouble to keep yourself from the attention of the Law. Then, your cousin gives you away.
Your cousin was interested in his ancestry. He gave some cheek cells to an ancestry company so that they could do a DNA trace. The ancestry company sends your cousin a report and stores his DNA profile in its database. Your cousin is not a happy man. He learns that he is a mutt, full of the bits and pieces of every race.
Off you go and commit your crime. You, the balding criminal, suffering from hair loss, leave a single strand of hair behind. The police find the strand and run a DNA check. Your DNA is not in the police database because you have made sure that the police never ever have a tissue sample from you.
Unknown to you, the police go to the ancestry company and run your hair strand through the company's database and they get a match with your cousin. Next thing you know, the police are breaking down your door and arresting you. The police traced you through your familial connection to your cousin.
Technology can be so annoying.