Craniosynostosis Molecular Analysis

Craniosynostosis occurs when the bones of a baby’s skull fuse together before the brain has stopped growing. Craniosynostosis can happen before the baby is born or during the first few months of life. Fusion at one or more locations and excessive growth at others leads to the distortion of the skull. This distortion may cause increased pressure and impaired blood flow in the brain, airway obstruction, impaired vision and hearing, learning difficulties and adverse psychological effects. Deformations in the skull may also be accompanied by abnormalities in the skeletal system, often in the hands and feet. Both genetic and environmental factors contribute to craniosynostosis. Most cases that are genetic in origin arise from new mutations. Genetic craniosynostosis syndromes show autosomal dominant inheritance, meaning that an affected individual has a 50 per cent chance of passing on the mutation to their offspring, who will also be affected.

Common craniosynostosis disorders may be caused by mutations in the fibroblast growth factor receptor 1, 2 or 3 (FGFR1, FGFR2, FGFR3) genes as well as a transcription factor gene called transcription factor TWIST1. The diagnosis of non-syndromic craniosynostosis is specifically based on the identification of a mutation in the fibroblast growth factor receptor 3 (FGFR3) gene. The diagnosis of Apert, Crouzon, Pfeiffer and Saethre-Chotzen Syndromes is based on clinical findings, although there is considerable clinical overlap. DNA-based testing of FGFR1 (chromosome 8p11.2-p12), FGFR2 (chromosome 10q25-q26), FGFR3 (chromosome 4p16.3), and TWIST1 (chromosome 7p21-p22) genes may be helpful in establishing the diagnosis in questionable cases.

See related information sheet:  Craniosynostosis