Pathogenic variants in TRIP4 and ASCC1, subunits of activating signal co-integrator 1 (ASC-1), were shown to cause prenatal-onset spinal muscular atrophy with congenital bone fractures (SMABF) type 1 and 2, respectively (MIM#616866, MIM#616867). Here, TRIP4 is linked to prenatal-onset spinal muscular atrophy with congenital bone fractures.