After sequencing the DNA of one of only four known families in the world to have a rare medical condition called adermatoglyphia, which leaves them without fingerprints, Eli Sprecher and his colleagues at the Tel Aviv Sourasky Medical Center identified the genetic mutation that causes the condition. According to research the group published in the American Journal of Human Genetics, nine out of 16 members of the family lacked fingerprints and all had mutations of a gene called SMARCAD1, which in its smaller form is only expressed in skin. Those nine individuals are also career criminals. Just kidding. From National Geographic:
The condition is also called immigration-delay disease, since a lack of fingerprints makes it difficult for people to cross international borders…
Other inherited diseases that result in a lack of fingerprints—such as Naegeli syndrome and dermatopathia pigmentosa reticularis—are caused by problems with the protein keratin-14.
These conditions "manifest not only with lack of fingerprints, but also with a number of other critical features—a thickening of the skin, problems with nail formation," Sprecher said.
By contrast, immigration-delay disease doesn't come with any side effects besides a minor reduction in the ability to sweat. In general, people with the disease "are otherwise completely healthy, like you and me."