15-90088605-C-G

Variant names:

• chr15-90088605-C-G
• rs1057519736
• NM_002168.4:c.516G>C

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PS1 PM2 PM5 PP3_Strong

The NM_002168.4(IDH2):​c.516G>C​(p.Arg172Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,894 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 risk factor (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R172W) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: IDH2 NM_002168.4 missense
• Clinical Significance: risk factor no assertion criteria provided O:1
• Conservation: PhyloP100: -0.829
• Publications: 161 publications found

Genes affected

IDH2 (HGNC:5383): (isocitrate dehydrogenase (NADP(+)) 2) 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 mitochondria. It plays a role in intermediary metabolism and energy production. This protein may tightly associate or interact with the pyruvate dehydrogenase complex. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2014]

IDH2 Gene-Disease associations (from GenCC):

• mitochondrial disease

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• d-2-hydroxyglutaric aciduria 2

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• D-2-hydroxyglutaric aciduria

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PS1: Transcript NM_002168.4 (IDH2) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr15-90088607-T-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 376439.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.981

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002168.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IDH2	NM_002168.4	MANE Select	c.516G>C	p.Arg172Ser	missense	Exon 4 of 11	NP_002159.2
	IDH2	NM_001289910.1		c.360G>C	p.Arg120Ser	missense	Exon 4 of 11	NP_001276839.1
	IDH2	NM_001290114.2		c.126G>C	p.Arg42Ser	missense	Exon 2 of 9	NP_001277043.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IDH2	ENST00000330062.8	TSL:1 MANE Select	c.516G>C	p.Arg172Ser	missense	Exon 4 of 11	ENSP00000331897.4
	IDH2	ENST00000864224.1		c.600G>C	p.Arg200Ser	missense	Exon 5 of 12	ENSP00000534283.1
	IDH2	ENST00000864227.1		c.585G>C	p.Arg195Ser	missense	Exon 5 of 12	ENSP00000534286.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461894 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727248

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112012

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions as Germline

Significance: risk factor

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
-	-	-	Acute myocardial infarction (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.32
CADD	Benign	20
DANN	Benign	0.96
DEOGEN2	Pathogenic	0.93	D
Eigen	Benign	-0.44
Eigen_PC	Benign	-0.77
FATHMM_MKL	Benign	0.53	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.50	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	0.37	D
MutationAssessor	Pathogenic	4.2	H
PhyloP100		-0.83
PrimateAI	Uncertain	0.79	T
PROVEAN	Pathogenic	-5.7	D
REVEL	Uncertain	0.57
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.91		Gain of disorder (P = 0.0759)
MVP		0.69
MPC		1.5
ClinPred		1.0	D
GERP RS		-3.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.97
gMVP		0.98
Mutation Taster		=5/95	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs1057519736; hg19: chr15-90631837; COSMIC: COSV57468772;