Mutation analysis of the ALD gene in seven Japanese families with X-linked adrenoleukodystrophy

The childhood cerebral form of X-linked adrenoleukodystrophy (X-ALD) is a severe congenital metabolic disease without a definite effective therapy except for hematopoietic stem cell transplantation in the appropriate disease stage. Seven Japanese families with X-ALD were analyzed for mutations in the ALD gene (ALD). Of the seven families, three were referred to us for prenatal diagnosis, four for carrier detection, and three for confirmation diagnosis of patients. By nucleotide sequencing and/or restriction analysis, all the subjects to be examined were successfully diagnosed. Six different missense mutations in ALD were identified. There was a G→A substitution (G512S) in two unrelated families, and a G→A (R617H), a C→T (R660W), a G→C (R163P), a C→T (S606L), or a G→A (G116E) substitution in each of the other five families. Among the six substitutions, five were those reported previously and the other was a novel mutation. In three families, prenatal diagnosis was carried out after genetic counseling.