Mutations in the cardiac isoform of TnT (TNNT2) are associated with familial HCM, dilated cardiomyopathy, or arthrogryposis (Thierfelder et al. 1994; Kamisago et al. 2000; Sehnert et al. 2002; Sung et al. 2003). Here, TNNT2 is linked to arthrogryposis.