rs777575504
Variant summary
Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2PM5PP3_ModeratePP5
The NM_002180.3(IGHMBP2):c.791G>A(p.Arg264His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000991 in 1,614,084 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R264C) has been classified as Likely pathogenic.
Frequency
Consequence
NM_002180.3 missense
Scores
Clinical Significance
Conservation
Publications
- autosomal recessive distal spinal muscular atrophy 1Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Genomics England PanelApp, Orphanet, Labcorp Genetics (formerly Invitae)
- Charcot-Marie-Tooth disease axonal type 2SInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
- hereditary peripheral neuropathyInheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
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ACMG classification
Our verdict: Likely_pathogenic. The variant received 7 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| IGHMBP2 | NM_002180.3 | c.791G>A | p.Arg264His | missense_variant | Exon 6 of 15 | ENST00000255078.8 | NP_002171.2 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| IGHMBP2 | ENST00000255078.8 | c.791G>A | p.Arg264His | missense_variant | Exon 6 of 15 | 1 | NM_002180.3 | ENSP00000255078.4 |
Frequencies
GnomAD3 genomes AF: 0.0000131 AC: 2AN: 152194Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.0000199 AC: 5AN: 251468 AF XY: 0.00000736 show subpopulations
GnomAD4 exome AF: 0.00000958 AC: 14AN: 1461890Hom.: 0 Cov.: 32 AF XY: 0.00000825 AC XY: 6AN XY: 727246 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000131 AC: 2AN: 152194Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1AN XY: 74354 show subpopulations
ClinVar
Submissions by phenotype
Autosomal recessive distal spinal muscular atrophy 1;C4015349:Charcot-Marie-Tooth disease axonal type 2S Pathogenic:1Other:1
This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 264 of the IGHMBP2 protein (p.Arg264His). This variant is present in population databases (rs777575504, gnomAD 0.02%). This missense change has been observed in individuals with clinical features of IGHMBP2-related conditions (PMID: 28902413; Invitae). ClinVar contains an entry for this variant (Variation ID: 577730). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt IGHMBP2 protein function with a positive predictive value of 95%. This variant disrupts the p.Arg264 amino acid residue in IGHMBP2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 26392352; Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -
Variant interpreted as Likely pathogenic and reported on 11-24-2020 by Invitae. GenomeConnect-Invitae Patient Insights Network assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. Registry team members make no attempt to reinterpret the clinical significance of the variant. Phenotypic details are available under supporting information. -
Charcot-Marie-Tooth disease axonal type 2S Pathogenic:1
Variant summary: IGHMBP2 c.791G>A (p.Arg264His) results in a non-conservative amino acid change located in the AAA+ ATPase domain (IPR003593) of the encoded protein sequence. Algorithms developed to predict the effect of missense changes on protein structure and function all suggest that this variant is likely to be disruptive. The variant allele was found at a frequency of 2e-05 in 251468 control chromosomes. c.791G>A has been observed in individual(s) affected with Charcot-Marie-Tooth disease axonal type 2S (Dohrn_2017, Internal data). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 28902413). ClinVar contains an entry for this variant (Variation ID: 577730). Based on the evidence outlined above, the variant was classified as likely pathogenic. -
Inborn genetic diseases Uncertain:1
The p.R264H variant (also known as c.791G>A), located in coding exon 6 of the IGHMBP2 gene, results from a G to A substitution at nucleotide position 791. The arginine at codon 264 is replaced by histidine, an amino acid with highly similar properties. This variant was detected in an individual with suspected hereditary neuropathy, who also had another variant in IGHMBP2; however, clinical details were limited, and it was unclear if the variants were in cis or trans (Dohrn MF et al. J Neurochem, 2017 12;143:507-522). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
not provided Uncertain:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at