Dermatopathia Pigmentosa Reticularis

A number sign (#) is used with this entry because of evidence that dermatopathia pigmentosa reticularis (DPR) is caused by heterozygous mutation in the keratin-14 gene (KRT14; 148066) on chromosome 17q21. One such family has been reported.

A closely related disorder, Naegeli-Franceschetti-Jadassohn syndrome (NFJS; 161000), is also caused by heterozygous mutation in the KRT14 gene.

Description

Dermatopathia pigmentosa reticularis is a rare heritable disorder consisting of a triad of cutaneous findings including reticulate hyperpigmentation, noncicatricial alopecia, and onychodystrophy. Variable features include adermatoglyphia, hypohidrosis or hyperhidrosis, and palmoplantar hyperkeratosis (Heimer et al., 1992).

Clinical Features

Heimer et al. (1992) described a family with 9 cases of dermatopathia pigmentosa reticularis distributed through 6 sibships of 4 generations. The diagnosis was confirmed by the authors in the 30-year-old proband and her son and daughter. In addition to the triad of reticulate hyperpigmentation, noncicatricial alopecia, and onychodystrophy, the proposita had adermatoglyphia, hypohidrosis, and punctate hyperkeratosis of the palms and soles. The family contained no instance of male-to-male transmission. Heimer et al. (1992) presented a figure demonstrating the lack of fingerprint patterns.

Dermatopathia pigmentosa reticularis is closely related to another autosomal dominant ectodermal dysplasia syndrome, Naegeli-Franceschetti-Jadassohn syndrome (NFJS; 161000) (Lugassy et al., 2006). Among the most distinctive characteristics of these syndromes is the complete absence of dermatoglyphics. Other shared features include a reticulate pattern of skin hyperpigmentation, thickening of the palms and soles (palmoplantar keratoderma), abnormal sweating, and other subtle developmental anomalies of the teeth, hair, and skin. DPR has been distinguished from NFJS by lifelong persistence of the skin hyperpigmentation, partial alopecia, and absence of dental anomalies (Heimer et al., 1992).

Mapping

Both dermatopathia pigmentosa reticularis and Naegeli-Franceschetti-Jadassohn syndrome map to a common 6-cM interval on 17q11.2-q21 (Whittock et al., 2000; Sprecher et al., 2002), supporting the suggestion that NFJS and DPR are allelic disorders (Itin and Lautenschlager, 1998). Lugassy et al. (2006) refined the location of the NFJS/DPR locus on 17q11.2-q21, with demonstration of a maximal lod score of 8.3 at marker D17S800 at a recombination fraction of 0.0.

Molecular Genetics

Lugassy et al. (2006) found that the NFJS/DPR locus harbored 230 genes, including a large cluster of keratin genes. They found heterozygous nonsense or frameshift mutations in the KRT14 gene (148066.0015, 148066.0016, and 148066.0019) that segregated with the disease traits in 5 families, 4 with NFJS and the 1 previously reported as DPR by Heimer et al. (1992).