Objectives: Current study was the first to report a consanguineous Iranian pedigree with ABCD1 mutation.
Methods: Targeted molecular analysis was initially performed in three affected individuals in one family suspected to have X-ALD due to chronic progressive spasticity. Upon confirmation of genetic diagnosis, further neurologic and genetic evaluation of all family members was done.
Results: A mutation in ABCD1 was identified in 35 affected individuals (out 96 pedigree members). The c. 253dup, in exon 1, leads to a frame shift and a premature stop codon at amino acid position 194 (p.Arg85Profs*110). Surprisingly, affected individuals in our cohort show some variability in phenotype, including childhood cerebral ALD, adrenomyeloneuropathy, and addison-only disease phenotypes, expanding the phenotype of X-ALD with p.Arg85Profs*110.
Conclusion: This report characterizes the clinical spectrum of an expanded Iranian pedigree with X-ALD due to an ABCD1 mutation. Given a high frequency of carriers in this region, we expect the prevalence of X-ALD to be higher, underscoring the importance of genetic counseling through reliable identification of heterozygous as well as homozygote females in consanguineous communities.
Keywords: ABCD1; Adrenoleukodystrophy; Mutation; X-linked.