Fibromatosis, Gingival, 4

Description

Hereditary gingival fibromatosis is a benign disorder manifested by a slowly progressive overgrowth of the oral gingival tissues, which results in the teeth being partially or totally engulfed by keratinized gingiva (summary by Zhu et al., 2007).

For general phenotypic information and a discussion of genetic heterogeneity of hereditary gingival fibromatosis, see GINGF1 (135300).

Clinical Features

Zhu et al. (2007) reported 2 large unrelated Chinese families with maternally inherited gingival fibromatosis. The disease phenotype was only manifested in the offspring of affected or carrier females, suggesting an imprinting effect. The families could be traced for 5 and 4 generations, respectively. Age at onset was within the first year of life.

Mapping

By 2-point linkage analysis in 2 large unrelated Chinese families with maternally inherited gingival fibromatosis, Zhu et al. (2007) mapped the disease locus to chromosome 11p15 (maximum lod score of 8.70 at D11S4046 in family 1 and 6.02 at D11S1318 in family 2). Haplotype analysis of both families identified a 10-cM critical region between D11S1984 and D11S1338. No mutations were identified in 15 genes within the interval, but Zhu et al. (2007) emphasized that chromosome 11p15 is a well-known imprinted region.