Blepharocheilodontic Syndrome 2

A number sign (#) is used with this entry because of evidence that blepharocheilodontic syndrome-2 (BCDS2) is caused by heterozygous mutation in the CTNND1 gene (601045) on chromosome 11q12.

For a general phenotypic description and a discussion of genetic heterogeneity of BCDS, see BCDS1 (119580).

Clinical Features

Ghoumid et al. (2017) studied 4 patients from 3 unrelated families with blepharocheilodontic syndrome and mutations in the CTNND1 gene. All of the patients had eyelid anomalies, including ectropion of the lower lids, euryblepharon, lagophthalmia, and distichiasis. In addition, all 4 showed typical facial dysmorphism with hypertelorism, flat face, and high forehead, and all had conical teeth and tooth agenesis. Three had cleft lip and palate, 3 had hair anomalies, and 1 had hypothyroidism due to hypoplasia or aplasia of the thyroid gland. None of the patients exhibited anal atresia or neural tube defects.

Molecular Genetics

From a cohort of 11 patients from 8 unrelated families with BCDS, Ghoumid et al. (2017) identified 4 patients from 3 families with heterozygous mutations in the CTNND1 gene (601045.0001-601045.0003). The remainder of the patients were heterozygous for mutations in the CDH1 gene (192090); see BCDS1, 119580. In 1 of the families, the mutation was inherited from an unaffected parent, suggesting incomplete penetrance. Ghoumid et al. (2017) stated that although the series was too small to establish genotype-phenotype correlations, they observed that eyelid anomalies were more severe in patients with CDH1 mutations than in those with CTNND1 mutations.