2-208248389-G-A

Variant names:

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM2PM5PP3_StrongPP5_Very_Strong

The NM_005896.4(IDH1):c.394C>T(p.Arg132Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000066 in 151,438 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 Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R132H) has been classified as Pathogenic.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

IDH1
NM_005896.4 missense

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:10O:1

Conservation

PhyloP100: 7.10

Variant links:

Genes affected

IDH1 (HGNC:5382): (isocitrate dehydrogenase (NADP(+)) 1) Isocitrate dehydrogenases catalyze the oxidative decarboxylation of isocitrate to 2-oxoglutarate. These enzymes belong to two distinct subclasses, one of which utilizes NAD(+) as the electron acceptor and the other NADP(+). Five isocitrate dehydrogenases have been reported: three NAD(+)-dependent isocitrate dehydrogenases, which localize to the mitochondrial matrix, and two NADP(+)-dependent isocitrate dehydrogenases, one of which is mitochondrial and the other predominantly cytosolic. Each NADP(+)-dependent isozyme is a homodimer. The protein encoded by this gene is the NADP(+)-dependent isocitrate dehydrogenase found in the cytoplasm and peroxisomes. It contains the PTS-1 peroxisomal targeting signal sequence. The presence of this enzyme in peroxisomes suggests roles in the regeneration of NADPH for intraperoxisomal reductions, such as the conversion of 2, 4-dienoyl-CoAs to 3-enoyl-CoAs, as well as in peroxisomal reactions that consume 2-oxoglutarate, namely the alpha-hydroxylation of phytanic acid. The cytoplasmic enzyme serves a significant role in cytoplasmic NADPH production. Alternatively spliced transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Sep 2013]

IDH1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr2-208248388-C-T is described in Lovd as [Pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.984

PP5

Variant 2-208248389-G-A is Pathogenic according to our data. Variant chr2-208248389-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 375891.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-208248389-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
IDH1	NM_005896.4 link	c.394C>T	p.Arg132Cys	missense_variant	Exon 4 of 10	ENST00000345146.7	NP_005887.2	O75874A0A024R3Y6
IDH1	NM_001282386.1 link	c.394C>T	p.Arg132Cys	missense_variant	Exon 4 of 10		NP_001269315.1	O75874A0A024R3Y6
IDH1	NM_001282387.1 link	c.394C>T	p.Arg132Cys	missense_variant	Exon 4 of 10		NP_001269316.1	O75874A0A024R3Y6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IDH1	ENST00000345146.7 link	c.394C>T	p.Arg132Cys	missense_variant	Exon 4 of 10	1	NM_005896.4	ENSP00000260985.2		O75874

Frequencies

GnomAD3 genomes

AF:

0.00000660

AC:

AN:

151438

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

Data not reliable, filtered out with message: AC0

AF:

0.00

AC:

AN:

1461688

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727162

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:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000660

AC:

AN:

151438

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

73904

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:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000378

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:10Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:3

Feb 01, 2017

CeGaT Center for Human Genetics Tuebingen

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Mar 01, 2021

Seattle Children's Hospital Molecular Genetics Laboratory, Seattle Children's Hospital

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant results in the substitution of arginine with cysteine at position 132 within the IDH1 protein. This variant is absent from large population cohorts (Genome Aggregation Database v2.1), and has been previously reported pathogenic in numerous individuals (PMID: 23485734, PMID: 30677207, PMID: 22057236, PMID: 22057234). In addition, functional studies demonstrate that the p.R132C mutation leads to neomorphic gain of function of the IDH1 protein (PMID: 19935646). -

Jul 24, 2019

Clinical Genetics and Genomics, Karolinska University Hospital

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Acute myeloid leukemia

Pathogenic:3

Molecular Diagnostics Laboratory, University of Rochester Medical Center

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: curation

- -

Mar 12, 2019

Molecular Diagnostics Laboratory, M Health Fairview: University of Minnesota

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 08, 2023

Sung Lab, Department of Medicine, Roswell Park Comprehensive Cancer Center

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Enchondromatosis;C0024454:Maffucci syndrome

Pathogenic:1

Aug 11, 2022

Greenwood Genetic Center Diagnostic Laboratories, Greenwood Genetic Center

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PS3, PS4, PM2, PP3 -

Maffucci syndrome

Pathogenic:1

Sep 08, 2023

Clinical Genomics Laboratory, Washington University in St. Louis

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The IDH1 c.394C>T (p.Arg132Cys) variant was identified at an allelic fraction consistent with somatic origin. It has been detected in several individuals affected with Maffucci syndrome and Ollier disease caused by somatic IDH1 c.394C>T (p.Arg132Cys) pathogenic variants (Pansuriya TC et al., PMID: 22057234; Nejo T et al., PMID: 30579273; Saiji E et al., PMID: 31240473; Amary MF et al. PMID: 22057236). This variant has been reported in the ClinVar database as pathogenic by eight submitters and as likely pathogenic by a single submitter (ClinVar ID: 375891) in both a germline and a somatic state. It also has been reported in 1150 cases in the cancer database (COSMIC ID: COSV61615256). IDH1 c.394C>T (p.Arg132Cys) is only observed on 1/151438 alleles in the general population (gnomAD v.3.1.2), indicating it is not a common variant. This variant resides within a region, amino acids 104-136, of IDH1 that is defined as a critical functional domain (Reitman ZJ et al., PMID: 20513808). Computational predictors indicate that the variant is damaging, evidence that correlates with impact to IDH1 function. Functional studies using cell lines show that this variant disrupts the resulting enzyme's ability to catalyze conversion of isocitrate to alpha-ketoglutarate (Dang L et al., PMID: 19935646). Other variants in this codon have been reported in individuals with Maffucci syndrome and Ollier disease and are considered pathogenic (Pansuriya TC et al., PMID: 22057234, ClinVar ID: 156444). Based on an internally-developed protocol informed by the ACMG/AMP guidelines (Richards S et al., PMID: 25741868) and gene-specific practices from the ClinGen Criteria Specification Registry, the IDH1 c.394C>T (p.Arg132Cys) variant is classified as pathogenic. -

Glioma susceptibility 1

Pathogenic:1

Center of Excellence in Genomics and Precision Dentistry, Faculty of Dentistry, Chulalongkorn University

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.394C>T p.(Arg132Cys) variant in IDH1 gene was identified in the proband’s hemangioma at low read depth by whole genome sequencing. This variant was categorized in the Tier I variants by AMP Standards and Guidelines for the Interpretation and Reporting of Sequence Variants in Cancer (Marilyn M. Li, 2017). -

Enchondromatosis

Pathogenic:1

May 09, 2022

Kasturba Medical College, Manipal, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Neoplasm

Other:1

Mar 04, 2025

Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital

Significance: -

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.99

BayesDel_addAF

Pathogenic

0.45

BayesDel_noAF

Pathogenic

0.42

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.90

D;D;D;.

Eigen

Uncertain

0.60

Eigen_PC

Uncertain

0.64

FATHMM_MKL

Uncertain

0.97

LIST_S2

Uncertain

0.94

.;.;D;D

M_CAP

Pathogenic

0.53

MetaRNN

Pathogenic

0.98

D;D;D;D

MetaSVM

Uncertain

0.73

MutationAssessor

Pathogenic

4.5

H;H;H;.

PrimateAI

Uncertain

0.75

PROVEAN

Pathogenic

-6.7

D;D;D;D

REVEL

Pathogenic

0.81

Sift

Uncertain

0.025

D;D;D;D

Sift4G

Pathogenic

0.0

D;D;D;.

Polyphen

0.26

B;B;B;.

Vest4

0.96

MutPred

0.94

Loss of MoRF binding (P = 0.0402);Loss of MoRF binding (P = 0.0402);Loss of MoRF binding (P = 0.0402);Loss of MoRF binding (P = 0.0402);

MVP

0.96

MPC

0.78

ClinPred

1.0

GERP RS

5.6

Varity_R

0.89

gMVP

0.98

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.51

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.51

Position offset: 34

DS_DL_spliceai

0.32

Position offset: -20

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