Identification of novel EIF2B mutations in Chinese patients with vanishing white matter disease

Vanishing white matter (VWM) disease, inherited in an autosomal recessive manner, is one of the most prevalent inherited leukoencephalopathies in childhood. It is a hereditary human disease resulting from the direct defects during protein synthesis, with the gene defects in EIF2B1-5 (identified in 2001-2002) encoding the five subunits of eukaryotic translation initiation factor (eIF2B alpha, beta, gamma, delta and epsilon), respectively. Most of the published studies were carried out in the white population. The analysis of clinical features and EIF2B mutation screening were performed in 11 Chinese patients for the first time. Mutations were identified exclusively in EIF2B5 and EIF2B3 in these patients, with six novel mutations, including five missense mutations (EIF2B5: c.185A>T, p.D62V; c.1004G>C, p.C335S; c.1126A>G, p.N376D; EIF2B3: c.140G>A, p.G47E; c.1037T>C, p.I346T) and one deletion leading to amino-acid deletion (EIF2B5: c.1827-1838del, p.S610-D613del). EIF2B3 mutation, accounting for 20% of the total number of mutations found in this study, is more prevalent than expected according to an earlier report (7%). A hot spot mutation in EIF2B3 was identified in this study. A unique EIF2B mutation spectrum in Chinese VWM patients was shown. A systemic study to assess mutation spectrum in different populations needs to be carried out.