In addition to the four probands, a thorough pedigree analysis led to the diagnosis of BTHS in two male family members, one (BTHS2 in Table 1; II: three in Family 1 in Fig. 2) with a confirmed TAZ mutation and the other one (BTHS6 in Table 1; IV: three in Family 4 in Fig. 2) with a presumptive diagnosis based on clinical signs of BTHS in a proven pedigree. Here, TAFAZZIN is linked to Barth syndrome.