rs376644749

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2PP3

The NM_002180.3(IGHMBP2):​c.217G>A​(p.Gly73Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000421 in 1,613,994 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/26 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000044 ( 0 hom. )

Consequence

IGHMBP2
NM_002180.3 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 1.50

Publications

0 publications found
Variant links:
Genes affected
IGHMBP2 (HGNC:5542): (immunoglobulin mu DNA binding protein 2) This gene encodes a helicase superfamily member that binds a specific DNA sequence from the immunoglobulin mu chain switch region. Mutations in this gene lead to spinal muscle atrophy with respiratory distress type 1. [provided by RefSeq, Jul 2008]
IGHMBP2 Gene-Disease associations (from GenCC):
  • autosomal recessive distal spinal muscular atrophy 1
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Ambry Genetics, Genomics England PanelApp, Orphanet, Labcorp Genetics (formerly Invitae)
  • Charcot-Marie-Tooth disease axonal type 2S
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Orphanet, Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • hereditary peripheral neuropathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
IGHMBP2NM_002180.3 linkc.217G>A p.Gly73Arg missense_variant Exon 2 of 15 ENST00000255078.8 NP_002171.2 P38935
IGHMBP2XM_047426881.1 linkc.217G>A p.Gly73Arg missense_variant Exon 2 of 15 XP_047282837.1
IGHMBP2XM_017017671.3 linkc.217G>A p.Gly73Arg missense_variant Exon 2 of 12 XP_016873160.1
IGHMBP2XM_005273976.3 linkc.217G>A p.Gly73Arg missense_variant Exon 2 of 9 XP_005274033.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
IGHMBP2ENST00000255078.8 linkc.217G>A p.Gly73Arg missense_variant Exon 2 of 15 1 NM_002180.3 ENSP00000255078.4 P38935

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152220
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000239
AC:
6
AN:
251474
AF XY:
0.0000441
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000438
AC:
64
AN:
1461774
Hom.:
0
Cov.:
31
AF XY:
0.0000509
AC XY:
37
AN XY:
727188
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33478
American (AMR)
AF:
0.0000224
AC:
1
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5726
European-Non Finnish (NFE)
AF:
0.0000531
AC:
59
AN:
1111966
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
4
8
11
15
19
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152220
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74370
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
41462
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.00376316), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000675
Hom.:
0
Bravo
AF:
0.0000416
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive distal spinal muscular atrophy 1;C4015349:Charcot-Marie-Tooth disease axonal type 2S Uncertain:1
Aug 15, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 73 of the IGHMBP2 protein (p.Gly73Arg). This variant is present in population databases (rs376644749, gnomAD 0.004%). This variant has not been reported in the literature in individuals affected with IGHMBP2-related conditions. ClinVar contains an entry for this variant (Variation ID: 534922). 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 not expected to disrupt IGHMBP2 protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Autosomal recessive distal spinal muscular atrophy 1 Uncertain:1
Apr 27, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

not provided Uncertain:1
Sep 01, 2019
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.13
BayesDel_addAF
Benign
-0.10
T
BayesDel_noAF
Benign
-0.25
CADD
Benign
19
DANN
Benign
0.88
DEOGEN2
Benign
0.18
T;.
Eigen
Benign
-0.82
Eigen_PC
Benign
-0.90
FATHMM_MKL
Benign
0.11
N
LIST_S2
Benign
0.77
T;T
M_CAP
Benign
0.085
D
MetaRNN
Benign
0.11
T;T
MetaSVM
Benign
-0.52
T
MutationAssessor
Benign
2.0
M;.
PhyloP100
1.5
PrimateAI
Benign
0.45
T
PROVEAN
Uncertain
-2.4
N;D
REVEL
Benign
0.15
Sift
Benign
0.29
T;T
Sift4G
Benign
0.53
T;T
Polyphen
0.17
B;.
Vest4
0.22
MutPred
0.52
Gain of MoRF binding (P = 0.0512);Gain of MoRF binding (P = 0.0512);
MVP
0.83
MPC
0.28
ClinPred
0.048
T
GERP RS
1.7
Varity_R
0.12
gMVP
0.32
Mutation Taster
=84/16
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.78
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.78
Position offset: 1
DS_DL_spliceai
0.21
Position offset: 39

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs376644749; hg19: chr11-68673667; API