title: A novel polyalanine expansion in FOXL2: the first evidence for a recessive form of the blepharophimosis syndrome (BPES) associated with ovarian dysfunction.
abstract: The blepharophimosis syndrome (BPES) is an autosomal dominant developmental disorder in which craniofacial/eyelid malformations are associated (type I) or not (type II) with premature ovarian failure (POF). Mutations in the FOXL2 gene, encoding a forkhead transcription factor, are responsible for both types of BPES. Heterozygous polyalanine expansions of +10 residues (FOXL2-Ala24) account for 30% of FOXL2 mutations and are fully penetrant for the eyelid phenotype. Here we describe the first homozygous FOXL2 mutation leading to a polyalanine expansion of +5 residues (FOXL2-Ala19). This novel mutation segregates in an Indian family where heterozygous mutation carriers are unaffected whereas homozygous individuals have the typical BPES phenotype, with proven POF in one female. Expression of the FOXL2-Ala19 protein in COS-7 cells revealed a significantly higher cytoplasmic retention compared to the wild-type protein. This is the first study providing genetic evidence for a recessive inheritance of BPES associated with ovarian dysfunction.
authors.affiliation: Department of Genetics, Aravind Medical Research Foundation, Aravind Eye Hospital, Madurai, India.
authors.forename: Jeyabalan
authors.initials: J
authors.lastname: Nallathambi
authors.forename: Lara
authors.initials: L
authors.lastname: Moumné
authors.forename: Elfride
authors.initials: E
authors.lastname: De Baere
authors.forename: Diane
authors.initials: D
authors.lastname: Beysen
authors.forename: Kim
authors.initials: K
authors.lastname: Usha
authors.forename: Periasamy
authors.initials: P
authors.lastname: Sundaresan
authors.forename: Reiner A
authors.initials: RA
authors.lastname: Veitia
mesh_terms: D000328:Adult; D000818:Animals; D016569:Blepharophimosis / Q000235:genetics* / Q000503:physiopathology; D019556:COS Cells; D002522:Chlorocebus aethiops; D042622:DNA Repeat Expansion / Q000235:genetics*; D005260:Female; D000074842:Forkhead Box Protein L2; D051858:Forkhead Transcription Factors / Q000235:genetics*; D005808:Genes, Recessive; D006801:Humans; D007194:India; D008297:Male; D009154:Mutation; D010375:Pedigree; D010455:Peptides / Q000235:genetics*; D016649:Primary Ovarian Insufficiency / Q000235:genetics* / Q000503:physiopathology; D013577:Syndrome
chemical_list: C421604:FOXL2 protein, human; D000074842:Forkhead Box Protein L2; D051858:Forkhead Transcription Factors; D010455:Peptides; C019529:polyalanine