How does the body make fingerprints?

Martha - How does the body make fingerprints? Listener McGraf in South Africa wanted to know whether the same prints get regenerated after an accident like a burn. Eli Sprecher, the Director of the Dermatology Unit at Tel Aviv Soraski Medical Centre says no.

Eli - Fingerprints as you know are characteristic of every individual human being but actually, they are not identical even in identical twins which means that the formation is influenced not only by genetic characteristics of the individual but also by some environmental stimuli. So they actually form as the result of some interaction between the upper part of the sin, which is called the epidermis, and the lower part of the skin which projects into the upper part of the skin and is called the dermis. And when the lower part of the skin is affected by any form of trauma - it might be a burn or treatment with some form of acid - then the signal transmitted from the dermis to the epidermis is lost. And as a consequence the fingerprints are either malformed or do not form at all.

Martha - And what do we know about how fingerprints are formed in development in the first place?

Eli - Now we know very, very little about what are the mechanisms and the signals at the molecular level that are regulating the formation of the fingerprints. Actually one of the only truly significant pieces of knowledge we have about that is coming from the study of a very rare disease where people are actually lacking fingerprints from birth. So by studying this disease it appears that there is one protein that is missing in these individuals, which is called SMARCAD1. And this is actually the only piece of information we have so far about the molecular mechanisms regulating the formation of fingerprints, so it's still quite a mystery.

Martha - That was Eli Sprecher from the Soraski Medical Centre in Tel Aviv.