Identification of a novel splice site mutation in the human hairless gene underlying atrichia with papular lesions.

Atrichia with Papular Lesions (APL) is a rare autosomal recessive disorder characterized by complete hair loss that begins shortly after birth with the development of papular lesions on various regions of the body. Since the establishment of hairless (HR) gene mutations as the cause of this disorder, several patients previously assumed to suffer from alopecia universalis have been subsequently diagnosed with APL. In this study we have identified a novel splicing mutation, IVS8+2T-->G, in the hairless gene. This mutation most likely abolishes normal splicing of exon 8 and potentially leads to out-of-frame skipping of this exon and a downstream premature termination codon (PTC). Our findings contribute to the growing body of HR mutations implicated in APL and provide further evidence for the differentiation of APL from alopecia universalis.

Novel compound heterozygous nonsense mutations in the hairless gene causing atrichia with papular lesions.

BACKGROUND: Atrichia with papular lesions (APL) is a rare autosomal recessive condition resulting from mutations in the hairless (HR) gene. OBJECTIVE: In the present study, we investigated the molecular basis of APL in a non-consanguineous Korean family. METHODS: Direct automated DNA sequencing of the HR gene and restriction digestion analysis were used to identify and confirm the mutation in our proband. RESULTS: Sequencing of the HR gene revealed two novel nonsense mutations in exons 2 and 4 which were subsequently confirmed via enzymatic restriction. No mutations have previously been detected in this population. CONCLUSION: The growing number of heterozygous mutations in non-consanguineous pedigrees supports the hypothesis that APL is more common than previously expected.

Atrichia with papular lesions resulting from compound heterozygous mutations in the hairless gene: A lesson for differential diagnosis of alopecia universalis.

BACKGROUND: Atrichia with papular lesions (APL) is a rare, autosomal recessive form of total alopecia in which mutations in the hairless (HR) gene have been shown to underlie the phenotype. OBJECTIVE: We suspect that APL is actually much more common than previously believed. We sought to investigate whether APL might also be found among patients in small families, particularly those giving a history of (1) normal hair at birth, which was shed and never regrew, and (2) "alopecia universalis" that is recalcitrant to any treatment. METHODS: We identified a small family of German origin in which 2 of 4 siblings were affected and gave this clinical history. Direct sequence analysis of the HR gene in the nuclear family was performed. RESULTS: Mutation analysis revealed distinct mutations on each allele of the HR gene. This is the first demonstration of compound heterozygous mutations underlying APL. CONCLUSION: These findings support the hypothesis that APL can exist in small nonconsanguineous families and may be masquerading clinically as alopecia universalis. Accurate discrimination between APL and alopecia universalis should prevent unnecessary treatment of patients affected with APL.