A progressive disorder characterized by short stature, myotonic myopathy, dystrophy of epiphyseal cartilages, joint contractures, blepharophimosis, unusual pinnae, myopia, and pigeon breast. Type 1 (SJS1) is caused by mutation in the gene encoding perlecan. The Silverman–Handmaker type of dyssegmental dysplasia is caused by a different mutation in the same gene and has a more severe phenotype. Neonatal Schwartz–Jampel syndrome type 2 (Stuve–Wiedemann syndrome) is a genetically distinct disorder with a more severe phenotype caused by mutation in the leukaemia inhibitory factor receptor (LIFR) gene.
Subjects: Medicine and Health.