Violetta, a 1920s sideshow performer with tetra-amelia syndrome
Tetra-amelia syndrome (tetra- + amelia), also called autosomal recessive tetraamelia,[1] is an extremely rare autosomalrecessive[2]congenital disorder characterized by the absence of all four limbs. Other areas of the body are also affected by malformations, such as the face, skull, reproductive organs, anus, lungs and pelvis.[1] The disorder can be caused by recessive mutations in the WNT3 or RSPO2 genes.[2][3]