Total submissions: 2
| Submitter | RCV | SCV | Clinical significance | Condition | Last evaluated | Review status | Method | Comment |
|---|---|---|---|---|---|---|---|---|
| Women's Health and Genetics/Laboratory Corporation of America, |
RCV001194117 | SCV001363404 | likely pathogenic | Metaphyseal chondrodysplasia, McKusick type | 2022-08-01 | criteria provided, single submitter | clinical testing | Variant summary: RMRP n.-20_1dup21involves the duplication of 21 nucleotides in the promoter region of the RMRP gene which is located between the TATA box (at position -33 to -25) and the transcription initiation site (at +1). Other insertions or duplications in the promoter region of RMRP have been classified as pathogenic (internally and in ClinVar). The variant allele was found at a frequency of 3.1e-05 in 128028 control chromosomes (gnomAD). n.-20_1dup21 has been reported in the literature in at least one individual affected with Cartilage-Hair Hypoplasia (e.g. Hermanns_2005). These data do not allow any conclusion about variant significance. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. However, many other insertions or duplications in the promoter region of RMRP have been reported in affected individuals in the literature (e.g. PMIDs: 21956908, 21396580) and have been demonstrated through functional studies to lead to reduced RMRP transcription (e.g. PMIDs: 11207361, 16254002). One other clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. |
| Invitae | RCV001244477 | SCV001417699 | pathogenic | Anauxetic dysplasia | 2023-12-30 | criteria provided, single submitter | clinical testing | This variant occurs in the RMRP gene, which encodes an RNA molecule that does not result in a protein product. This variant is present in population databases (no rsID available, gnomAD 0.02%). While this particular variant has not been reported in the literature, it is located in the promoter region between the TATA box and the transcription initiation site, and other insertions and duplications immediately upstream of the coding sequence have been reported in individuals affected with cartilage-hair hypoplasia-anauxetic dysplasia (CHH-AD) spectrum disorders (PMID: 16244706, 11207361, 12107819). ClinVar contains an entry for this variant (Variation ID: 929121). While functional studies for this variant have not been reported, experimental analyses using patient derived cells, as well as in vitro transfection studies, have shown that promoter insertions result in silencing of RMRP transcription and reduced expression of the gene product (PMID: 11207361, 16254002). For these reasons, this variant has been classified as Pathogenic. |