Tetra-amelia syndrome (sometimes known as TETAMS) is a very rare disorder characterized by the absence of all four limbs. ("Tetra" is the Greek word for "four," and "amelia" refers to the failure of an arm or leg to develop before birth.)

Variants (also called mutations) in two genes have been found to cause tetra-amelia syndrome. Variants in the WNT3 gene cause tetra-amelia syndrome type 1 and variants in the RSPO2 gene cause tetra-amelia syndrome type 2.

Tetra-amelia syndrome is a very rare condition that has been described in only a few families worldwide. Because this condition is so severe, the frequency is reported to be at least 30 times higher among stillbirths than among live births.

Tetra-amelia syndrome appears to have an autosomal recessive pattern of inheritance. Autosomal recessive inheritance means both copies of the gene in each cell have mutations. The parents of an individual with tetra-amelia syndrome each carry one copy of the mutated gene, but do not show signs and symptoms of the condition.

Published Date: February 17, 2023
Published By: National Institutes of Health