Rhizomelic Chondrodysplasia Punctata

Rhizomelic chondrodysplasia punctata (RCDP) is a type of peroxisomal disorder which impairs the normal development of many parts of the body. It is characterized by shortening of the bones in the upper arms and thighs (rhizomelia). People with RCDP have very poor growth and often develop joint deformities (contractures) that make the joints stiff and painful. Other major features include distinctive facial features, intellectual disability, clouding of the lenses of the eyes (cataracts), heart defects, and respiratory problems. There are 5 types of RCDP, classified according to the associated gene mutations:

RCDP1 with PEX7 gene
RCDP2 with GNPAT gene
RCDP3 with AGPS gene
RCDP4 (peroxisomal fatty acyl-CoA reductase 1 disorder) with FAR1 gene
RCDP5 with PEX5 gene  

All these genes are involved in the formation and function of sac-like cell structures called peroxisomes that contain enzymes needed to break down many substances, including fatty acids known as plasmalogens. Deficiency of plasmalogen affects bone growth. Inheritance is autosomal recessive. There is no cure for RCDP. Treatment is  symptomatic and may include physiotherapy and orthopedic procedures, eye surgery, and nutritional plans. For example, RCDP1 patients may need diet restriction of phytanic acid.