Novel HSPG2 mutations causing Schwartz­Jampel syndrome type 1 in a Chinese family: A case report.

Schwartz-Jampel syndrome type 1 (SJS1) is a rare autosomal recessive disease caused by mutations in the gene heparan sulfate proteoglycan 2 (HSPG2; also known as basement membrane­specific heparin sulfate). In the present study, a 10­year­old female SJS1 proband from a Chinese family, who was diagnosed by X­ray and physical examination, was recruited. The key clinical features of the patient with SJS1 included short stature, joint contractures, pigeon breast, and myotonia that led to progressive stiffness of the face and limbs; barely discernible kyphosis was also noted. Genetic testing using whole exome sequencing and Sanger sequencing was performed for the proband and family members. A total of 2 novel mutations (c.8788G>A; p.Glu2930Lys and c.11671+5G>A) in the HSPG2 gene were identified in the proband. The family members harboring 1 heterozygous mutation in HSPG2 did not exhibit any skeletal abnormalities. The results of the present study suggested that the compound heterozygous mutations in HSPG2 may be responsible the induction of SJS1, and demonstrated the genotype­phenotype associations between mutations in the HSPG2 gene and clinical characteristics of SJS1.