Refinement of the locus for autosomal dominant hereditary gingival fibromatosis (GINGF) to a 3.8-cM region on 2p21

Hereditary gingival fibromatosis (HGF, MIM 135300; approved gene symbol GIN GF) is an oral disease characterized by enlargement of gingiva. Recently, a locus for autosomal dominant HGF has been mapped to an 11-cM region on chr omosome 2p21. In the current investigation, we genotyped four Chinese HGF f amilies using polymorphic microsatellite markers on 2p21. The HOMOG test pr ovided evidence for genetic homogeneity, with evidence for linkage in four families (heterogeneity versus homogeneity test HOMOG, chi(2) = 0.00). A cu mulative maximum two-point lod score of 5.04 was produced with marker D2S39 0 at a recombination frequency of theta = 0 in the four linked families. Ha plotype analysis localized the hereditary gingival fibromatosis locus withi n the region defined by D2S352 and D2S2163. This region overlaps by 3.8 cM with the previously reported HGF region. Single-strand conformation polymor phism and sequence analysis of the coding region of cytochrome P450 1B1 (CY P1B1) excluded it as a likely candidate gene. (C) 2000 Academic Press.