Short-limbed dwarfism with bowing, combined immune deficiency, and late onset aplastic anaemia caused by novel mutations in the RMPR gene

[...]there is still a group of cases described as kyphomelic dysplasia, which do not fit the profile of these or other disorders that manifest as dwarfism and kyphomelia. 16 The cases can be distinguished from campomelic dysplasia by the extraskeletal manifestations, mental retardation, ambiguous genitalia, severe tibial bowing, and hypoplastic scapulae in the latter, 17 and from femoral hypoplasia-unusual facies syndrome by the hypoplasia of the femur. 18 Several single case reports that show a related but still different phenotype have been described. 19- 21 Short-limbed dwarfism with normal intelligence does also occur in cartilage-hair hypoplasia (CHH; MIM 250250). CHH presenting in infancy can be difficult to diagnose. 23, 24 Mutations in the RMRP gene that codes for an RNA subunit of the mitochondrial RNA processing (MRP) RNAse complexes are the cause of CHH, with a common "Finnish" mutation +70A->G (A70G) in many of the known CHH patients. 25, 26 Here we report on a case with short-limb dwarfism diagnosed as having kyphomelic dysplasia in infancy, who developed severe aplastic anaemia, concurring with a combined immune deficiency of late onset.