Our fingerprints are unique, and not even identical twins share the same prints. They’ve been used by people making their mark for thousands of years – as well as their more recent use in crime fighting and identification – and appear while we’re still in the womb. Yet very little is known about how our fingerprints form. The skin on our fingertips is made of two main layers – the epidermis on top, and the dermis beneath. Researchers currently think that as a foetus develops, the epidermis grows faster than the dermis. This makes it fold and buckle, forming a ridged pattern shaped by swirling forces inside the womb. There’s one genetic clue too. People with a faulty version of a gene called SMARCAD1 have no fingerprints, making life difficult for them at border crossings. But exactly how the gene is involved in shaping fingerprints remains a scientific mystery.
Written by Kat Arney
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