The cause of<unk>  is unknown. However, an interruption of the embryonic blood supply to the arteries that lie under the collarbone (subclavian arteries) at about the 46th day of embryonic development is the prevailing theory. The subclavian arteries normally supply blood to embryonic tissues that give rise to the chest wall and hand. Variations in the site and extent of the disruption may explain the range of signs and symptoms that occur in<unk> . Abnormality of an embryonic structure called the apical ectodermal ridge, which helps direct early limb development, may also be involved in this disorder.
Poland syndrome
Möbius syndrome
Rett syndrome
Hanhart syndrome
Pallister–Hall syndrome
Robinow syndrome
Krabbe disease
Foster Kennedy syndrome