[Phenotypic and genetic analysis of a Chinese pedigree affected with Oral-facial-digital syndrome]

To explore the clinical phenotype and genetic basis for a Chinese pedigree affected with Oral-facial-digital syndrome type I (OFD1).

A pedigree with OFD1 who presented at Hebei General Hospital on March 17, 2021 was selected as the subject. Clinical data of the child was collected. Trio-whole exome sequencing (trio-WES) was carried out for the proband and members of her pedigree, and candidate variant was verified by Sanger sequencing.

The proband has featured hypotelorism, broad nasal root, flat nasal tip, lobulated tongue, tongue neoplasia, camptodactyly of left fifth finger, syndactyly of right fourth and fifth fingers, and delayed intellectual and language development. Trio-WES revealed that the proband and her daughter, sister and mother have harbored a heterozygous c.224A>G (p.Asn75Ser) variant of the OFD1 gene. The same variant was not found among healthy members from her pedigree.

The c.224A>G (p.Asn75Ser) variant probably underlay the OFD1 in this pedigree. Above discovery has enriched the spectrum of OFD1 gene variants.