A Gene Locus Responsible for Reticulate Pigmented Anomaly of the Flexures Maps to Chromosome 17p13.3

Reticulate pigmented anomaly of the flexures (RPAF), also called Dowling–Degos disease, is a rare autosomal-dominant cutaneous disorder characterized by spotted and reticulate pigmentation of the flexures. The gene, or even the chromosomal location, for RPAF has not yet been identified. In this study, one Chinese family with RPAF was identified and subjected to a genomewide screen for linkage analysis. We identified a locus at chromosome 17p13.3 with a maximum two-point limit of detection score of 3.61 at markers D17S831and D17S1866 (at recombination fraction θ=0.00). Haplotype analyses indicated that the disease gene is located within the 6.8 cM region distal to D17S1798. It is the first locus identified for RPAF. This study provides a map location for isolation of a disease gene causing RPAF.