What is "cri du chat"

n. A congenital syndrome in humans, characterized by a catlike mewl in affected infants, effected by an absence of some genetic material on the fifth chromosome.

Cri du chat syndrome, also known as chromosome 5p deletion syndrome, 5p− (said minus) syndrome or Lejeune’s syndrome, is a rare genetic disorder due to a missing part (deletion) of chromosome 5. Its name is a French term (cat-cry or call of the cat) referring to the characteristic cat-like cry of affected children. It was first described by Jérôme Lejeune in 1963. The condition affects an estimated 1 in 50,000 live births, strikes all ethnicities, and is more common in females by a 4:3 ratio.