A novel PIEZO2 mutation in a fetus from a Chinese family with Gordon syndrome

Abstract

We describe a fetus from a Chinese family whose parents were both healthy but showed multiple malformations, including clubfoot, camptodactyly, micrognathia, and cleft palate. Genomic DNA was extracted from the peripheral blood of the proband's parents and skeletal muscle tissue from the aborted fetus to determine the diagnosis and underlying cause. Whole-exome sequencing revealed that the fetus was heterozygous for a novel variant of uncertain significance in exon 56 (c.8576G>A; p.Trp2859*) of the Piezo-type mechanosensitive ion channel component 2 gene (PIEZO2) (NM_001378183.1). A diagnosis of Gordon syndrome (GS) was made from the presence of this variant and ultrasonic manifestation. Sanger sequencing of the proband's parents resulted in normal chromatograms, suggesting that this was either a de novo variant in the fetus or, less likely, the result of germline mosaicism in the proband's mother or father. This is the first description of GS caused by a PIEZO2 variant in which the fetus was the proband. A prenatal diagnosis of GS can be established by fetal ultrasound examination combined with genetic testing.