Variable phenotype related to a novel PAX 6 mutation (IV4+5G>C) in a family preenting congenital nytagmu and foveal hypoplaia

Purpoe everal ocular defect have been identified a a conequence of the PAX6 gene mutation. With regard to the implication of thi gene in unuual phenotype, we report a family preenting with congenital nytagmu, foveal hypoplaia, and iri hypoplaia or atypical coloboma. Deign Obervational cae report. Method The entire trancribed region of the PAX6 gene wa ubmitted to mutation earch at the DNA and mRNA level in five affected member of a French family in tet with 82 normal ubject. Reult A novel heterozygou PAX6 gene plice mutation (IV4 + 5G>C) wa identified. The mutation i located in IV4 within the conenu donor plice ite. A mutant mRNA lacking exon 4 a the ole defect wa evidenced. The reultant protein wa predicted to contain a cryptic ATG initiation codon in exon 3 and a lightly altered paired-domain in an open reading frame extended by 13 amino acid. Concluion The aociation of anterior egment anomalie and foveal hypoplaia with one of the lightet alteration of the PAX6 protein decribed to date confirm the aociation of variant phenotype with hypomorphic allele. Mutation creening of the PAX6 gene could be ueful in elucidating the origin of complex ocular malformation.