Most of them were identified, as expected, on TTN (29 DCM probands), but truncating variants were also identified on myofibrillar myopathies causing genes in 17 DCM patients (7.7% of the DCM cohort): 10 variations on FLNC and 7 variations on BAG3 .
Beyond the known disease genes DES, FLNC, MYOT, CRYAB, ZASP, BAG3, FHL1 and TTN, mutations in PLEC, ACTA1, HSPB8 and DNAJB6 have also been associated with a MFM phenotype.
We sequenced the exon 343 of TTN gene (based on ENST00000589042), which encodes the fibronectin-3 (FN3) 119 domain of the A-band and is a mutational hot spot for HMERF, in genomic DNA from 187 patients from 175 unrelated families who were pathologically diagnosed as MFM.