TLCD3B and Duchenne muscular dystrophy: We replicated these findings in another dataset of patients with DMD (1 to 8 years of age) (17) in which subunits of SPT (SPTLC1 and SPTLC2) along with CERS2, the ceramide synthase responsible for production of very-long-chain sphingolipids, were consistently induced (Fig. 1C).