NM_002180.3:c.166C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_002180.3(IGHMBP2):​c.166C>T​(p.Arg56Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,613,986 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R56H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000011 ( 0 hom. )

Consequence

IGHMBP2
NM_002180.3 missense

Scores

7
12

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.994

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: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.21580347).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
IGHMBP2NM_002180.3 linkc.166C>T p.Arg56Cys missense_variant Exon 2 of 15 ENST00000255078.8 NP_002171.2 P38935
IGHMBP2XM_047426881.1 linkc.166C>T p.Arg56Cys missense_variant Exon 2 of 15 XP_047282837.1
IGHMBP2XM_017017671.3 linkc.166C>T p.Arg56Cys missense_variant Exon 2 of 12 XP_016873160.1
IGHMBP2XM_005273976.3 linkc.166C>T p.Arg56Cys 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.166C>T p.Arg56Cys missense_variant Exon 2 of 15 1 NM_002180.3 ENSP00000255078.4 P38935

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152170
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251484
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000109
AC:
16
AN:
1461816
Hom.:
0
Cov.:
31
AF XY:
0.0000165
AC XY:
12
AN XY:
727206
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.000174
AC:
15
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53412
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5760
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111960
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
2
4
5
7
9
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:
0.0000131
AC:
2
AN:
152170
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74340
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
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:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Autosomal recessive distal spinal muscular atrophy 1;C4015349:Charcot-Marie-Tooth disease axonal type 2S Uncertain:1
Sep 06, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 56 of the IGHMBP2 protein (p.Arg56Cys). This variant is present in population databases (rs201649839, gnomAD 0.01%). 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: 466582). 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. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.052
T
BayesDel_noAF
Benign
-0.11
CADD
Benign
19
DANN
Uncertain
0.98
DEOGEN2
Uncertain
0.55
D;.
Eigen
Benign
-0.38
Eigen_PC
Benign
-0.33
FATHMM_MKL
Benign
0.48
N
LIST_S2
Uncertain
0.89
D;D
M_CAP
Benign
0.041
D
MetaRNN
Benign
0.22
T;T
MetaSVM
Uncertain
-0.11
T
MutationAssessor
Uncertain
2.6
M;.
PhyloP100
0.99
PrimateAI
Uncertain
0.51
T
PROVEAN
Uncertain
-3.4
D;D
REVEL
Benign
0.27
Sift
Benign
0.048
D;T
Sift4G
Benign
0.070
T;T
Polyphen
0.23
B;.
Vest4
0.28
MutPred
0.46
Loss of MoRF binding (P = 0.0053);Loss of MoRF binding (P = 0.0053);
MVP
0.88
MPC
0.27
ClinPred
0.55
D
GERP RS
2.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.24
gMVP
0.49
Mutation Taster
=62/38
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs201649839; hg19: chr11-68673616; API