[P2-186] Two Novel ABCD1 Mutations in Chinese Families with X-linked Adrenoleukodystrophy
[Background]: X-linked adrenoleukodystrophy (X-ALD) is a fatal X-linked recessive disorder that is caused by mutations in the ATP-binding cassette, subfamily D, member 1 gene (ABCD1). X-ALD is characterized by abnormal function of the peroxisomes, which leads to accumulation of the very long chain fatty acids (VLCFAs) in all tissues especially in the adrenal cortex and the myelin of the central nervous system. Childhood cerebral form of ALD (ccALD) is the most frequent phenotype. In this study, ABCD1 mutations were identified in three unrelated Chinese families with X-ALD. [Methods]: Mutation screening by PCR amplification and sequencing was performed in three unrelated Chinese families who exhibited typical features of X-ALD. The laboratory and radiological investigations were conducted simultaneously. [Results]: Two novel ABCD1 mutations were identified including one splice site mutation c.1489-9delC in IVS5 preceding exon 6 and one missense mutation p.H97R in exon 1. In addition, one previously described missense mutation p.R518Q was also identified. All of the probands’ mothers were found to be heterozygous carriers of the corresponding mutations. [Conclusions]: Mutations in ABCD1 were responsible for X-ALD in these Chinese families. Our findings are useful for understanding the genetic basis of Chinese patients with X-ALD.