RNase MRP (also called RMRP) is an enzymatically active ribonucleoprotein with two distinct roles in eukaryotes.

In the nucleus, it is involved in precursor rRNA processing, where it cleaves the internal transcribed spacer 1 between 18S and 5.8S rRNAs.

[2] Mutations in the RNA component of RNase MRP cause cartilage–hair hypoplasia, a pleiotropic human disease.

RNase MRP also demonstrated cleavage ability of the 5′-UTR of CLB2 mRNA that allows for rapid 5′-to-3′ degradation by XRN1, an exoribonuclease enzyme.

RNAse P is found in both eukaryotes and prokaryotes and it cleaves a pre-tRNA to generate the mature 5’ end of the tRNA.

Mutations in the RNA component of RNase MRP cause cartilage–hair hypoplasia(CHH), a pleiotropic human disease.

The first type is when an insertion, duplication, or triplication occurs at the promoter of the RNAse MRP gene between the TATA box and the transcription initiation site.

The fact that there is not often a mutation in the promoter region in both alleles shows the lethality of not having this RNA present that is transcribed by RNAse MRP.

[9] These two diseases do differ in that MDWH lacks immunodeficiency and other skeletal features found in CHH patients.

KD is rather similar to several forms of MCD in that it exhibits combined immune deficiency and aplastic anemia.

OS is also commonly accompanied by enlarged lymphoid tissues, protracted diarrhea, failure to thrive, and eosinophilia.

Patients with OS are immunodeficient meaning their immune system is compromised and cannot properly fight infections resulting in serious secondary illnesses.