Rhizomelic Chondrodysplasia Punctata, Type 1 (PEX7)
Rhizomelic chondrodysplasia punctata, type 1 is an autosomal recessive disorder caused by pathogenic variants in the gene PEX7. While it has been reported in populations worldwide, it is more prevalent in Caucasian individuals. Onset is at birth. This disorder is characterized by short stature due to shortening of the femur and humerus, and abnormalities of the long bones. Patients often have joint contractures, characteristic facial features, cataracts, seizures, growth deficiency, and severe intellectual disability. The maximum life expectancy is about ten years, although death may occur in infancy or childhood. Some patients have been reported to have a milder phenotype with less severe bone changes, growth deficiency and intellectual disability. Some pathogenic PEX7 variants have been reported to be associated with either the more severe or the milder form of the disease and therefore the severity of the disease may be able to be predicted depending on the genotype of the patient.
For information about carrier frequency and residual risk, please see the residual risk table.