rs1057518588

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_002180.3(IGHMBP2):c.547+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000936 in 1,602,756 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 30)

Exomes 𝑓: 0.0000090 ( 0 hom. )

Consequence

IGHMBP2
NM_002180.3 splice_donor, intron

Scores

Splicing: ADA: 1.000

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: 4.75

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 18 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 11-68908632-G-A is Pathogenic according to our data. Variant chr11-68908632-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 373749.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr11-68908632-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	Effect	Exon rank	MANE	Protein	UniProt
IGHMBP2	NM_002180.3 link	c.547+1G>A	splice_donor_variant, intron_variant	Intron 4 of 14	ENST00000255078.8	NP_002171.2	P38935
IGHMBP2	XM_047426881.1 link	c.547+1G>A	splice_donor_variant, intron_variant	Intron 4 of 14		XP_047282837.1
IGHMBP2	XM_017017671.3 link	c.547+1G>A	splice_donor_variant, intron_variant	Intron 4 of 11		XP_016873160.1
IGHMBP2	XM_005273976.3 link	c.547+1G>A	splice_donor_variant, intron_variant	Intron 4 of 8		XP_005274033.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IGHMBP2	ENST00000255078.8 link	c.547+1G>A		splice_donor_variant, intron_variant	Intron 4 of 14	1	NM_002180.3	ENSP00000255078.4		P38935

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152142

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251352

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135876

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:

0.0000653

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000896

AC:

AN:

1450614

Hom.:

Cov.:

AF XY:

0.0000111

AC XY:

AN XY:

722270

show subpopulations

Gnomad4 AFR exome

AF:

0.0000301

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000465

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000635

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152142

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74312

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000624

Hom.:

Bravo

AF:

0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Autosomal recessive distal spinal muscular atrophy 1

Pathogenic:2

Dec 19, 2017

Rady Children's Institute for Genomic Medicine, Rady Children's Hospital San Diego

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This splice variant is predicted to impact a canonical splice donor site. This variant has been classified by a clinical laboratory as likely pathogenic in ClinVar (Variation ID 373749). This variant has not been previously reported literature nor has it been functionally characterized to our knowledge; however, several other splice variants in this gene have been previously described in association with disease. Multiple in silico splice prediction tools predict a damaging effect of the variant. It is present in the heterozygous state in the gnomAD population database at a frequency of 0.003% (1/30934). Based on the combined evidence, the c.547+1G>A is classified as likely pathogenic. -

Jan 21, 2018

Service de Pédiatrie - Neurologie et infectiologie - Toulouse, CHU de Toulouse - Hôpital des Enfants

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: case-control

It is a splice mutation (at the beginning of intron 4, hence probably on a splice site), whose dysfunction might generate a premature stop codon. It occurs early in the sequence: in the intron 4, for a total of 15 exons. Moreover, it is located in the main functional domain "DNA helicase domain" of the protein IGHMB2, at a specific location where ATP binding sites are concentrated. -

not provided

Pathogenic:2

Dec 12, 2016

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

A novel c.547+1 G>A variant that is likely pathogenic has been identified in the IGHMBP2 gene. The c.547+1 G>A variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. The c.547+1 G>A variant is not observed in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). The c.547+1 G>A splice site variant in the IGHMBP2 gene destroys the canonical splice donor site in intron 4. It is predicted to cause abnormal gene splicing, either leading to an abnormal message that is subject to nonsense-mediated mRNA decay, or to an abnormal protein product if the message is used for protein translation. Therefore, this variant is likely pathogenic; however, the possibility that it is benign cannot be excluded. -

Mar 01, 2024

CeGaT Center for Human Genetics Tuebingen

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

IGHMBP2: PVS1, PM2, PM3 -

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

Pathogenic:1

Jul 01, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 4 of the IGHMBP2 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in IGHMBP2 are known to be pathogenic (PMID: 14681881, 25439726, 25568292). This variant is present in population databases (no rsID available, gnomAD 0.006%). Disruption of this splice site has been observed in individual(s) with clinical features of IGHMBP2-related conditions (PMID: 28902413, 31019026; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 373749). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.50

BayesDel_noAF

Uncertain

0.090

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Pathogenic

0.93

Eigen_PC

Pathogenic

0.70

FATHMM_MKL

Pathogenic

0.99

GERP RS

4.3

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.93

SpliceAI score (max)

0.99

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.99

Position offset: -1

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