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Updated: Apr 21, 2026
In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
Published on: August 20, 2019
Branchio-oculo-facial syndrome: a three generational family with markedly variable phenotype including neonatal
Hannah L Titheradge1, Chirag Patel, Nicola K Ragge
1aDepartment of Clinical Genetics, Birmingham Women's NHS Foundation Trust, Birmingham bDepartment of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK cGenetic Health Queensland, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia.
Abstract:
Branchio-oculo-facial syndrome (BOFS) is a rare autosomal dominant condition with variable expressivity, caused by mutations in the TFAP2A gene. We report a three generational family with four affected individuals. The consultand has typical features of BOFS including infra-auricular skin nodules, coloboma, lacrimal duct atresia, cleft lip, conductive hearing loss and typical facial appearance. She also exhibited a rare feature of preaxial polydactyly. Her brother had a lethal phenotype with multiorgan failure. We also report a novel variant in TFAP2A gene. This family highlights the variable severity of BOFS and, therefore, the importance of informed genetic counselling in families with BOFS.
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