Only a small number of genes have been associated with FND phenotypes until now, the first gene being EFNB1, related to craniofrontonasal syndrome (CFNS) with craniosynostosis in addition, and more recently the aristaless-like homeobox genes ALX3, ALX4, and ALX1, which have been related with distinct phenotypes named FND1, FND2, and FND3 respectively.
We report a family with vertical transmission from mother to son of mild frontonasal dysplasia phenotype caused by a novel ALX4 gene mutation (c.1080-1089_delGACCCGGTGCinsCTAAGATCTCAACAGAGATGGCAACT, p.Asp326fsX21).This is the first report of a frontonasal phenotype related to a heterozygous mutation in ALX4.