Simian crease

A simian crease is a single line that runs across the palm of the hand. A single palmar crease appears in approximately 1 out of 30 people. A single palmar crease is often a normal finding. However, it may also be associated with: Down syndrome, Aarskog syndrome, Cohen syndrome, Fetal alcohol syndrome, Trisomy 13, Rubella syndrome, Turner syndrome, Klinefelter syndrome, Pseudohypoparathyroidism, Gonadal dysgenesis, and Cri du chat syndrome.