OBJECTIVE: To explore the clinical characteristics and genetic etiology of a child with Oral-facial-digital syndrome type Ⅰ(OFDSⅠ). METHODS: A child with OFDSⅠ who received treatment at the Women and Children's Hospital Affiliated to Ningbo University in March 2023 was selected as the study subject. A retrospective research method was used to collect the clinical data of the child. Peripheral venous blood samples were collected from the child, her parents and sister. Genomic DNA was extracted, and whole exome sequencing (WES) was performed. Candidate variants were validated using Sanger sequencing for familial verification. According to the Standards and Guidelines for the Interpretation of Sequence Variants developed by the American College of Medical Genetics and Genomics (ACMG) (hereinafter referred to as the "ACMG Guidelines"), the pathogenicity of the candidate variant was rated. This study was approved by the Medical Ethics Committee of Ningbo University Affiliated Women and Children's Hospital (Ethic No.: EC 2024-063). RESULTS: The child was a prematurely born female with deformities of the oral cavity, fingers, and toes. She was admitted to the Neonatal Department of the Hospital where she was born due to shortness of breath 15 minutes after birth. The WES results indicated that the child has harbored a heterozygous c.710dup (p.Y238Vfs*2) frameshifting variant of the OFD1 gene. Sanger sequencing confirmed that neither of the child's parents nor her sister had carried the same variant. According to the ACMG guidelines, the variant was rated as pathogenic (PVS1+PS4_Moderate+PM2-Supporting+PM6_Supporting+PP4). CONCLUSION Children with OFDSⅠ have clinical features such as oral, finger, and toe deformities. The c.710dup (p.Y238Vfs*2) variant of the OFD1 gene probably underlay the OFDSⅠ in this child. Above result has enriched the mutational spectrum of the OFD1 gene.
Humans ; Female ; Orofaciodigital Syndromes/genetics* ; Exome Sequencing ; Retrospective Studies ; Mutation ; Child ; Proteins

OBJECTIVE: To explore the clinical phenotype and genetic basis for a Chinese pedigree affected with Oral-facial-digital syndrome type I (OFD1). METHODS: 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. RESULTS: 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. CONCLUSION The c.224A>G (p.Asn75Ser) variant probably underlay the OFD1 in this pedigree. Above discovery has enriched the spectrum of OFD1 gene variants.
Humans ; Female ; Pedigree ; Orofaciodigital Syndromes/genetics* ; East Asian People ; Phenotype ; Heterozygote ; Mutation ; China