Consistent with the lower unconjugated SUMO4 levels in fibroblasts of SUMO4 variant carrier TALS004-01, SUMOylation of VCP by SUMO4 was significantly reduced in these cells compared to sex- and age-matched non-ALS control fibroblasts (Fig. 1h, i). The gene discussed is VCP; the disease is amyotrophic lateral sclerosis.