Congenital red hair heterochromia in the background of blond scalp hair.

We report a case of isolated patchy red hair heterochromia of the scalp in a healthy 6-year-old boy. Isolated patchy scalp hair heterochromia is the presence of two or more colors of hair in the same individual, thought to be due to genetic mosaicism although no specific etiology has been widely accepted. We have outlined a basic approach to diagnosing different types of heterochromia for clinical application.