Missing Chromosome disorders

Chromosomes of Turner Syndrome

Most disorders of missing chromosomes involve only partially missing chromosomes, with one exception:

Turner syndrome happens when the baby girl has a single X chromosome instead of a pair of X chromosomes. People with Turner syndrome tend to be short, have normal intelligence, and may need hormone therapy to induce puberty. Many need fertility help to get pregnant.

Diagram showing missing arm of a chomosome

Prader-willi Syndrome is caused by a partial absence of the 15th chromosome. Most of the symptoms are behavioral, including constant hunger, which can result in obesity and an increased risk of type 2 diabetes.

Cri-du-chat (French for “cry of a cat”) syndrome babies have a partially missing 5th chromosome. It can be fairly severe or fairly mild. It’s name comes from the characteristic way that newborns with this syndrome sound like a cat when they cry.

Most of these happen randomly and are not inherited.