There are typically two creases in the palm, but in some people, only one crease is present. A single palmar crease occurs in about 1 out of 30 people, but is also frequently associated with other conditions such as Down syndrome, Aarskog syndrome or fetal alcohol syndrome.
Review Date 7/28/2022
Updated by: Charles I. Schwartz MD, FAAP, Clinical Assistant Professor of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, General Pediatrician at PennCare for Kids, Phoenixville, PA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.