A 24-year-old man came to a dermatology clinic in southern India with skin that had been darkening in a netlike pattern since birth, thinning scalp hair, and fragile fingernails and toenails. There was another detail that is easy to miss and rarely seen: he had no fingerprints.
When doctors took a fuller family history, they learned that his 28-year-old sister had lived with the same netlike pigmentation, damaged nails and missing fingerprints since birth.
