ClinVar

In affected members of 2 families with BPES type II (110100), and in a sporadic male BPES patient, Crisponi et al. (2001) identified a 30-bp duplication at position 909 to 938. Amino acids 224 to 234 were duplicated. In the 2 families with multiple cases, affected females transmitted the trait to the next generation.

Ramirez-Castro et al. (2002) identified this mutation in affected members of 2 families with BPES type II from a historically isolated population in northwest Colombia. The genotype/phenotype correlation in the families was consistent with a proposal that BPES type I is caused by truncating mutations leading to haploinsufficiency, while BPES type II is caused by mutations generating elongated protein products (see also 605597.0008). This duplication has also been described as recurrent in unrelated familial and sporadic BPES cases in Europe; its recurrence may be related to the secondary structure of the particular DNA region.

In both a family and sporadic case of BPES type II from Algeria, Dollfus et al. (2003) identified this mutation.

In an 18-month-old girl with sporadic BPES and bilateral type 1 Duane syndrome (see 126800), Vincent et al. (2005) identified heterozygosity for a 30-bp duplication, which they designated 672_701dup30 based on numbering from the ATG start codon, resulting in a duplication of 10 alanine residues at codon 224 in the FOXL2 gene.