A novel compound WISP3 mutation in a Chinese family with progressive pseudorheumatoid dysplasia

Abstract

Background: Progressive pseudorheumatoid dysplasia (PPD) is an extremely rare autosomal recessive genetic disease caused by mutation of the Wnt1-inducible signaling pathway protein 3 (WISP3) gene. Here, we characterize the clinical manifestations and features of PPD and screen for WISP3 mutations.

Materials and methods: We performed genetic testing for PPD in a Chinese family, after investigating the clinical particulars and family history, in addition to 200 healthy individuals, who served as the controls for this study. All 5 exons and the exon-intron boundaries of the WISP3 gene were amplified by polymerase chain reaction (PCR) and sequenced directly.

Results: We identified a missense mutation (c.667T>G, p.C223G) in the maternal allele and a nonsense mutation (c.756C>A, p.C252X) in the paternal allele in the two affected individuals. To our knowledge, the mutation c.756C>A has not been reported previously. In these patients, there was a specific period when their condition markedly improved after having been very serious. Moreover, severe compression of lumbar spinal cord led to conspicuous spinal disorders in the proband.

Conclusions: Our study suggests that novel C223G and C252X mutations in exon 4 of the WISP3 gene are responsible for PPD in Chinese patients. Furthermore, we report certain unique phenotypic characteristics in our patients.

Keywords: Mutation; Progressive pseudorheumatoid dysplasia; Spinal disorder; WISP3.