Tetra-amelia

Tetra-amelia syndrome is a rare occurrence of human characterized by a failure in the embryonic formation, which implies the absence of all four limbs. Malformations in other parts of the body such as head, heart, skeletal, genitalia, and lungs may occur concurrently, so that most of the carriers do not survive after birth. The term comes from the Greek "tetra" four, and "amelia", or failure in limb development.

An example of this anomaly is the motivational speaker Nick Vujicic, Australian.

Causes

In some patients with the syndrome, was identified a mutation in the gene WNT3. In other cases, the cause was not identified, been identified as possibly related to WNT3 unknown mutations in the gene or other genes related to embryonic development of members.

In most cases, tetra-Amelia appears to follow the pattern of an autosomal recessive, or both parents of an individual carrier carrying the mutant gene, without presenting symptoms.