MASA syndrome

MASA syndrome A syndrome named for its characteristics: mental retardation, aphasia, shuffling gait, and adducted thumbs. Features of the syndrome include mental retardation and aphasia (lack of speech); adducted (clasped) thumbs, absent extensor pollicis longus and/or brevis muscles to the thumb, shuffling gait, and leg spasticity; small body size; and lumbar lordosis (swayback). MASA is inherited as an X-linked trait, and so it affects mainly boys. Also known as clasped thumbs and mental retardation, congenital clasped thumbs with mental retardation, adducted thumbs with mental retardation, and Gareis-Mason syndrome. See also adducted thumbs.