More than 15 existing studies on cases carrying homozygous or compound heterozygous NBAS gene mutations revealed the broad phenotypic spectrum of NBAS mutation-based diseases, ranging from isolated recurrent ALF to a multisystemic disease with short stature, skeletal dysplasia, facial dysmorphism, immunological abnormalities, Pelger-Huët anomaly, and optic nerve atrophy resembling SOPH syndrome (Fig. 4)4–18. The gene discussed is NBAS; the disease is skeletal dysplasia.