11-68929204-T-C

Position:

chr11-68929204-T-C

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM1PM2PP3_ModeratePP5_Very_Strong

The NM_002180.3(IGHMBP2):c.1082T>C(p.Leu361Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000117 in 1,613,386 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 Pathogenic (★★).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

IGHMBP2
NM_002180.3 missense

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:8U:2

Conservation

PhyloP100: 7.69

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM1

In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 9 uncertain in NM_002180.3

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.922

PP5

Variant 11-68929204-T-C is Pathogenic according to our data. Variant chr11-68929204-T-C is described in ClinVar as [Pathogenic]. Clinvar id is 245627.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr11-68929204-T-C is described in Lovd as [Pathogenic]. Variant chr11-68929204-T-C is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
IGHMBP2	NM_002180.3 linkuse as main transcript	c.1082T>C	p.Leu361Pro	missense_variant	8/15	ENST00000255078.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
IGHMBP2	ENST00000255078.8 linkuse as main transcript	c.1082T>C	p.Leu361Pro	missense_variant	8/15	1	NM_002180.3	P1

Frequencies

GnomAD3 genomes

AF:

0.0000920

AC:

AN:

152160

Hom.:

Cov.:

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:

0.000206

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000558

AC:

AN:

250754

Hom.:

AF XY:

0.0000590

AC XY:

AN XY:

135628

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000123

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000119

AC:

174

AN:

1461108

Hom.:

Cov.:

AF XY:

0.000122

AC XY:

AN XY:

726918

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000150

Gnomad4 OTH exome

AF:

0.000116

GnomAD4 genome

AF:

0.0000919

AC:

AN:

152278

Hom.:

Cov.:

AF XY:

0.0000672

AC XY:

AN XY:

74458

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000206

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000781

Hom.:

Bravo

AF:

0.0000945

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.0000576

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.000237

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:8Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Athena Diagnostics	Nov 02, 2016	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Oct 18, 2022	Published functional studies demonstrate a damaging effect with severe loss of enzymatic activity compared to wild type (Eckart et al., 2012); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 18802676, 26922252, 14681881, 21353777, 17431882, 14506069, 16964485, 23566544, 33210134, 36077311, 27535533, 22157136, 25439726, 22965130, 24388491) -
Pathogenic, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Jul 21, 2022	- -

Autosomal recessive distal spinal muscular atrophy 1;C4015349:Charcot-Marie-Tooth disease axonal type 2S

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 11, 2024	This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 361 of the IGHMBP2 protein (p.Leu361Pro). This variant is present in population databases (rs201060167, gnomAD 0.01%). This missense change has been observed in individual(s) with distal spinal muscular atrophy type 1 and/or spinal muscular atrophy with respiratory distress type 1 (PMID: 14506069, 14681881, 18802676). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 245627). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on IGHMBP2 protein function. Experimental studies have shown that this missense change affects IGHMBP2 function (PMID: 22157136). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Oct 31, 2018	- -

Inborn genetic diseases

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 30, 2020

The p.L361P variant (also known as c.1082T>C), located in coding exon 8 of the IGHMBP2 gene, results from a T to C substitution at nucleotide position 1082. The leucine at codon 361 is replaced by proline, an amino acid with similar properties. This alteration has been reported in individuals presenting with early-onset disease, such as SMARD1 (Grohmann K et al. Ann. Neurol., 2003 Dec;54:719-24; Guenther UP et al. Hum. Mutat., 2007 Aug;28:808-15; Guenther UP et al. J. Mol. Med., 2009 Jan;87:31-41; Pitt M et al. Brain, 2003 Dec;126:2682-92). These individuals were reported to have a second IGHMBP2 alteration; however, the phase of the two alterations was only confirmed to be in trans in two individuals (Guenther UP et al. Hum. Mutat., 2007 Aug;28:808-15; Guenther UP et al. J. Mol. Med., 2009 Jan;87:31-41). Functional studies demonstrated that the p.L361P alteration leads to a severe loss of enzymatic activity of the IGHMBP2 protein (Eckart M et al. Pediatrics, 2012 Jan;129:e148-56). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Autosomal recessive distal spinal muscular atrophy 1

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Sep 02, 2022

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with Charcot-Marie-Tooth disease, axonal, type 2S (MIM#616155) and neuronopathy, distal hereditary motor, type VI (MIM#604320). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from leucine to proline. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (15 heterozygotes, 0 homozygotes). (SP) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0600 - Variant is located in the annotated AAA domain (DECIPHER). (I) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. This variant has been reported multiple times as pathogenic, and observed in compound heterozygous individuals with spinal muscular atrophy with respiratory distress (ClinVar, PMID: 23566544, PMID: 22157136). (SP) 1002 - This variant has moderate functional evidence supporting abnormal protein function. Recombinant protein has been proven to result in significantly reduced enzyme activity through an ATPase assay (PMID: 22157136). (SP) 1201 - Heterozygous variant detected in trans with a second pathogenic heterozygous variant (p.(Cys496*)) in a recessive disease. (SP) 1206 - This variant has been shown to be paternally inherited (by trio analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Charcot-Marie-Tooth disease axonal type 2S

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

May 10, 2022

Variant summary: IGHMBP2 c.1082T>C (p.Leu361Pro) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 5.6e-05 in 250754 control chromosomes. c.1082T>C has been reported in the literature in individuals affected with diaphragmatic palsy, Charcot-Marie-Tooth Disease or hereditary motor neuropathy. These data indicate that the variant is likely to be associated with disease. Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Charcot-Marie-Tooth disease

Uncertain:1

Uncertain significance, no assertion criteria provided

provider interpretation

Inherited Neuropathy Consortium

- -

Distal spinal muscular atrophy

Uncertain:1

Uncertain significance, no assertion criteria provided

literature only

Inherited Neuropathy Consortium

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.88

BayesDel_addAF

Pathogenic

0.26

BayesDel_noAF

Pathogenic

0.36

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.66

Eigen

Uncertain

0.53

Eigen_PC

Uncertain

0.35

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.88

M_CAP

Uncertain

0.22

MetaRNN

Pathogenic

0.92

MetaSVM

Uncertain

0.75

MutationAssessor

Pathogenic

2.9

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.69

PROVEAN

Uncertain

-4.1

REVEL

Pathogenic

0.79

Sift

Uncertain

0.017

Sift4G

Pathogenic

0.0010

Polyphen

1.0

Vest4

0.94

MVP

0.99

MPC

0.97

ClinPred

0.92

GERP RS

5.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.92

gMVP

0.91

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over