Identification of the forkhead transcriptional factor 2 (FOXL2) gene mutations in four Chinese families with blepharophimosis syndrome

PURPOSE To determine the genetic origin of disease in four Chinese families with blepharophimosis syndrome. METHODS Four Han Chinese families with blepharophimosis syndrome were ascertained and patients underwent complete physical and ophthalmic examinations. Blood samples were collected and genomic DNA was extracted. Sequence analysis of the forkhead transcriptional factor 2 (FOXL2) gene was performed by direct sequencing and mutations were analyzed. RESULTS Three mutations in FOXL2 were found in four families, including c.672_701dup30 (p.Ala224_Ala234dup10), c.313C>A (p.N105H), and c.430G>T (p.R144W). The c.672_701dup30 (p.Ala224_Ala234dup10) mutation was reported previously and predicted to result in expansions of the polyalanine tract. The mutations of c.313C>A (p. N105H) and c.430G>T (p.R144W) are two novel missense mutations. CONCLUSIONS Our study further supports the view that the expansion of the polyalanine tract is the hotspot of mutations within FOXL2. The two novel missense mutations detected in this study will expand the mutation spectrum of the FOXL2 gene and contribute to the research on the molecular pathogenesis of FOXL2.