chr8-39918873-C-T

Variant names:

• chr8-39918873-C-T
• rs1807226208
• NM_002164.6:c.362C>T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_002164.6(IDO1):​c.362C>T​(p.Pro121Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000132 in 151,976 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 Uncertain significance (★).

• Frequency: Genomes: 𝑓 0.000013 (0 hom., cov: 32)
• Consequence: IDO1 NM_002164.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.62

Genes affected

IDO1 (HGNC:6059): (indoleamine 2,3-dioxygenase 1) This gene encodes indoleamine 2,3-dioxygenase (IDO) - a heme enzyme that catalyzes the first and rate-limiting step in tryptophan catabolism to N-formyl-kynurenine. This enzyme acts on multiple tryptophan substrates including D-tryptophan, L-tryptophan, 5-hydroxy-tryptophan, tryptamine, and serotonin. This enzyme is thought to play a role in a variety of pathophysiological processes such as antimicrobial and antitumor defense, neuropathology, immunoregulation, and antioxidant activity. Through its expression in dendritic cells, monocytes, and macrophages this enzyme modulates T-cell behavior by its peri-cellular catabolization of the essential amino acid tryptophan.[provided by RefSeq, Feb 2011]

ENSG00000253939 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.948

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
IDO1	NM_002164.6	c.362C>T	p.Pro121Leu	missense_variant	Exon 4 of 10	ENST00000518237.6	NP_002155.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IDO1	ENST00000518237.6	c.362C>T	p.Pro121Leu	missense_variant	Exon 4 of 10	1	NM_002164.6	ENSP00000430950.1

Frequencies

GnomAD3 genomes AF: 0.0000132 AC: 2 AN: 151976 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000656

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 Cov.: 31

GnomAD4 genome AF: 0.0000132 AC: 2 AN: 151976 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74214

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000656

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: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Dec 25, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.362C>T (p.P121L) alteration is located in exon 4 (coding exon 4) of the IDO1 gene. This alteration results from a C to T substitution at nucleotide position 362, causing the proline (P) at amino acid position 121 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.24
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.0
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.58	.;D;D
Eigen	Pathogenic	0.68
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.94	D;.;D
M_CAP	Benign	0.046	D
MetaRNN	Pathogenic	0.95	D;D;D
MetaSVM	Uncertain	0.18	D
MutationAssessor	Pathogenic	3.4	.;M;M
PrimateAI	Uncertain	0.55	T
PROVEAN	Pathogenic	-9.7	D;D;D
REVEL	Uncertain	0.50
Sift	Uncertain	0.0030	D;D;D
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	.;D;D
Vest4		0.66, 0.65
MutPred		0.82		Loss of methylation at K116 (P = 0.0491);Loss of methylation at K116 (P = 0.0491);Loss of methylation at K116 (P = 0.0491);
MVP		0.84
MPC		0.27
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.88
gMVP		0.32

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

Other links and lift over

dbSNP: rs1807226208; hg19: chr8-39776392;