These included a pathogenic variant in TAFAZZIN:c.284+5G>A (Barth syndrome), a variant of unknown significance (VUS) in MYBPC3:c.1224-80G>A and 2 compound heterozygous LP variants in LZTR1 (LZTR1:c.1943-256C>T and LZTR1:c1261-3C>G) in a patient with clinical features of RASopathy. This evidence concerns the gene MYBPC3 and Barth syndrome.