Phenotypic variation in trismus-pseudocamptodactyly syndrome caused by a recurrent MYH8 mutation.

We report a 20-year-old man with trismus-pseudocamptodactyly (TPS) syndrome who was found to have the same MYH8 mutation, p.R674Q, described in previous families with TPS syndrome and in one family with a Carney complex variant, trismus and pseudocamptodactyly. This patient had facial asymmetry, ptosis and downslanting palpebral fissures and multiple joint involvement, with bilateral hip dysplasia, reduced elbow supination, vertical tali and talipes in addition to the classical findings of trismus and pseudocamptodactyly. These findings broaden the phenotype associated with p.R674Q mutations and support the use of MYH8 testing in patients with a clinical diagnosis of TPS syndrome.