@entity56022 are a clinically heterogeneous group of rare @entity74 with overlapping features including @entity5656 and @entity5105 . We ascertained five extended pedigrees with different phenotypes for a linkage study. Three families presented with @entity57969 , and one with @entity56022 and @entity2055 . Another family had @entity57969 associated with variable @entity8820 plaques. Despite their phenotypic differences, both @entity57969 and @entity56022 with @entity2055 map to a common region in 1p34-p35. Multipoint linkage and haplotype analyses place @entity57969 between the marker D1S496 and D1S186 with a maximum LOD score of 12.88. Our linkage results provide compelling evidence for genetic homogeneity among families of mixed European and French-Canadian origin. In contrast, results excluded Greither's disease from the established @entity57969 gene region indicating genetic heterogeneity of @entity56022 . Based on recombinations, two genes assigned to 1p34-p35 were excluded: cartilage matrix protein and avian myelocytosis viral oncogene. @entity45450 ( @entity45450 ), a member of the connexin gene family, maps within the @entity57969 region and is an attractive candidate gene. Direct sequencing of the coding region of @entity45450 in four @entity1 revealed several variations, including a novel polymorphism within the 5' cytoplasmic domain, but no pathogenic mutations were found, thus excluding @entity45450 as a candidate. There is evidence, however, that other epidermally expressed connexins cluster in this region, and one may yet be determined to play a role in the pathogenesis of @entity57969 .

Linkage studies in XXXX : fine mapping, genetic heterogeneity and analysis of candidate genes.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity45450 :: ('2701', 'Gene') :: ['Connexin-37', 'GJA4'] @entity8820 :: ('MESH:C566153', 'Disease') :: ['hyperkeratotic'] @entity5656 :: ('MESH:D017488', 'Disease') :: ['hyperkeratosis'] @entity5105 :: ('MESH:D004890', 'Disease') :: ['erythema'] @entity74 :: ('MESH:D030342', 'Disease') :: ['autosomal dominant disorders of cornification'] @entity56022 :: ('MESH:C535738', 'Disease') :: ['erythrokeratodermia', 'Erythrokeratodermias', 'erythrokeratodermias'] @entity57969 :: ('MESH:D056266', 'Disease') :: ['localized erythrokeratodermia variabilis', 'erythrokeratodermia variabilis', 'Greither disease'] @entity2055 :: ('MESH:D001259', 'Disease') :: ['ataxia']
@entity56022 :: (MESH:C535738,Disease) :: ['erythrokeratodermias']
