Molecular genetic screening of MBS1 locus on chromosome 13 for microdeletions and exclusion of FGF9, GSH1 and CDX2 as causative genes in patients with Moebius syndrome

Moebius syndrome is a rare disorder primarily characterized by congenital facial palsy, frequently accompanied by ocular abduction anomalies, and occasionally associated with orofacial, limb and musculoskeletal malformations. Abnormal development of cranial nerves V through XII underlines the disease pathogenesis. Although some investigations suggested that a causative gene may lie on 13q12.2–q13, there have been no molecular studies targeting possible microdeletions in this region to date. In the present study, we performed microdeletion analyses on 13q12.11–q13 in nine patients, and sequenced three candidate genes in nineteen patients for functional relevance and further resolution of our screening. We ruled out microdeletions on the critical region as a common cause of Moebius syndrome and excluded FGF9, GSH1 and CDX2 genes.