Tooth Agenesis, Selective, 5

For a general phenotypic description and a discussion of genetic heterogeneity of selective tooth agenesis, see STHAG1 (106600).

Clinical Features

Wang et al. (2000) described a form of agenesis of permanent teeth in a large Chinese kindred. Penetrance was estimated to be 0.88, and no significant clinical manifestations other than the oligodontia were found. Agenesis ranged from a few teeth to the entire set of teeth, involved only the permanent teeth, and usually appeared at age 7 or 8 years, when primary teeth are normally replaced by permanent teeth. Some of the affected individuals had development of first and second molars. In some cases, it appeared that the remaining teeth were not permanent teeth; instead, they were primary and sometimes remained until the forties. Because of the impression that the tooth abnormality in this kindred had been hitherto undescribed, Wang et al. (2000) referred to it as 'He-Zhao deficiency.' The kindred came from a small village in Xunyi County of Shaanxi Province in northwest China.

Mapping

By linkage analysis in the large Chinese kindred with selective tooth agenesis studied by Wang et al. (2000), Liu et al. (2001) found maximum 2-point and multipoint lod scores of 13.29 at theta = zero (on marker D10S196) and 18.09 (between markers D10S1772 and D10S1766), respectively. Haplotype analysis narrowed the assignment to a 5.5-cM interval flanked by markers D10S604 and D10S568 on chromosome 10q11.2.