Novel OBSL1 Variant in a Chinese Patient with 3M Syndrome and the c.458dupG Mutation May Be a Potential Hotspot Mutation in the Chinese Population.

3M syndrome is an autosomal recessive disorder characterized by short stature and skeletal developmental abnormalities. In this study, a Chinese patient with 3M syndrome was presented. A novel OBSL1 (obscurin-like 1 gene) variant was found. The patient is a 2-year-old girl who presented with short stature and had intrauterine growth retardation and low birth weight. Gene analysis revealed compound heterozygote mutations in the OBSL1 gene: c.458dupG (p.L154Pfs*100) and c.427dupG (p.A143Gfs*111). The c.427dupG mutation is novel. The c.458dupG mutation has been documented in 5 cases, occurring only in Chinese individuals, indicating ethnic specificity. In cases of short-statured children presenting intrauterine growth retardation, low birth weight, and skeletal developmental abnormalities, 3M syndrome should be considered. The c.458dupG mutation might be a hotspot mutation in the Chinese population.