Preferred Label : Palmoplantar keratoderma, epidermolytic, 1;
Symbol : EPPK1;
CISMeF acronym : TYLOSIS; EPPK;
Type : Phenotype, molecular basis known;
Alternative titles and symbols : Keratoderma, epidermolytic palmoplantar; Palmoplantar keratoderma, vorner type; Hyperkeratosis, localized epidermolytic; Keratosis palmaris et plantaris familiaris; Palmoplantar keratoderma, epidermolytic, with knuckle pads; PPKE; TYLOSIS;
Description : Palmoplantar keratoderma (PPK) is a common hereditary cutaneous disorder characterized
by marked hyperkeratosis on the surface of palms and soles (Hennies et al., 1995).
PPK has been classified into diffuse, focal, and punctate forms according to the pattern
of hyperkeratosis on the palms and soles (Lucker et al., 1994). Diffuse PPK develops
at birth or shortly thereafter and involves the entire palm and sole with a sharp
cutoff at an erythematous border; there are no lesions outside the volar skin, and,
in particular, no follicular or oral lesions. In contrast, focal PPK is a late-onset
form in which focal hyperkeratotic lesions develop in response to mechanical trauma;
an important distinguishing feature is the presence of lesions at other body sites,
e.g., oral and follicular hyperkeratosis (Stevens et al., 1996). Palmoplantar keratodermas
can be further subdivided histologically into epidermolytic and nonepidermolytic PPK
(Risk et al., 1994). - Genetic Heterogeneity of Palmoplantar Keratoderma Nonepidermolytic
palmoplantar keratoderma (NEPPK; 600962) is caused by mutation in the KRT1 gene. A
focal form of NEPPK (FNEPPK; 613000) is caused by mutation in the KRT16 gene (148067).
The diffuse Bothnian form of NEPPK (PPKB; 600231) is caused by mutation in the AQP5
gene (600442). The Nagashima type of nonepidermolytic diffuse PPK (PPKN; 615598) is
caused by mutation in the SERPINB7 gene (603357). A generalized form of epidermolytic
hyperkeratosis (EHK; 113800), also designated bullous congenital ichthyosiform erythroderma
(BCIE), is caused by mutation in the keratin genes KRT1 and KRT10 (148080). For a
discussion of punctate PPK, see 148600; for a discussion of striate PPK, see 148700.;
Inheritance : Autosomal dominant;
Molecular basis : Caused by mutation in the keratin 1 gene (KRT1, 139350.0014); Caused by mutation in the keratin 9 gene (KRT9, 607606.0001);
Prefixed ID : #144200;
Origin ID : 144200;
UMLS CUI : C1840427;
Automatic exact mappings (from CISMeF team)
- Currated CISMeF NLP mapping
- DO Cross reference
- Genes related to phenotype
- HPO term(s)
- ORDO concept(s)
- See also inter- (CISMeF)
- Semantic type(s)
- UMLS correspondences (same concept)
- Validated automatic mappings to BTNT
- Validated automatic mappings to NTBT
