Evaluation of Sporadic and Familial Cases with Craniofrontonasal Syndrome: A Wide Clinical Spectrum and Identification of a Novel EFNB1 Gene Mutation

Abstract

Craniofrontonasal syndrome (CFNS) is a rare X-linked genetic disorder which is characterized by coronal synostosis, widely spaced eyes, a central nasal groove, and various skeletal anomalies. Mutations in the <i>EFNB1</i> gene in Xq13.1 are responsible for familial and sporadic cases. In the present study, we aimed to evaluate the clinical characteristics and molecular results of 4 patients with CFNS. Genomic DNA was extracted from the peripheral blood lymphocytes of all patients and their parents, and Sanger sequencing of the <i>EFNB1</i> gene was performed. A novel <i>EFNB1</i> gene mutation (c.65delG; p.Cys22SerfsTer24) was detected in a newborn who had only dysmorphic facial features and bicornuate uterus. The other 3 patients (2 familial cases and 1 sporadic case) shared the same mutation (c.196C&#x3e;T; p.R66X). However, the clinical features of these patients were highly variable. Additionally, central (meso-axial) polydactyly and deep palmar creases were detected, which have not been previously reported. CFNS has a wide clinical spectrum, but there is no clear genotype-phenotype correlation. However, central (meso-axial) polydactyly and deep palmar creases may be part of the clinical spectrum seen in CFNS. In addition, our findings expand the mutational spectrum in patients with CFNS.