Genetic Variant IDO1:p.Phe185Leu (chr8-39923486-C-G) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The NM_002164.6(IDO1):c.555C>G(p.Phe185Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000094 in 1,595,690 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000076 ( 0 hom. )

Consequence

IDO1
NM_002164.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.654

Variant links:

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]

IDO1 links:

ENSG00000253939 (HGNC:):

ENSG00000253939 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.06046951).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
IDO1	NM_002164.6 link	c.555C>G	p.Phe185Leu	missense_variant	Exon 7 of 10	ENST00000518237.6	NP_002155.1	P14902A0A348GSI3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IDO1	ENST00000518237.6 link	c.555C>G	p.Phe185Leu	missense_variant	Exon 7 of 10	1	NM_002164.6	ENSP00000430950.1		P14902

Frequencies

GnomAD3 genomes

AF:

0.0000264

AC:

AN:

151688

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:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000803

AC:

AN:

249194

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135204

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:

0.0000177

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000762

AC:

AN:

1444002

Hom.:

Cov.:

AF XY:

0.00000417

AC XY:

AN XY:

719466

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:

0.0000100

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000264

AC:

AN:

151688

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74036

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:

0.0000588

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000198

Hom.:

Bravo

AF:

0.0000567

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000122

AC:

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Jan 20, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.555C>G (p.F185L) alteration is located in exon 7 (coding exon 7) of the IDO1 gene. This alteration results from a C to G substitution at nucleotide position 555, causing the phenylalanine (F) at amino acid position 185 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

Uncertain

0.47

BayesDel_addAF

Benign

-0.30

BayesDel_noAF

Benign

-0.65

CADD

Benign

0.74

DANN

Benign

0.57

DEOGEN2

Benign

0.081

T;T

Eigen

Benign

-1.1

Eigen_PC

Benign

-1.2

FATHMM_MKL

Benign

0.026

LIST_S2

Benign

0.33

.;T

M_CAP

Benign

0.0030

MetaRNN

Benign

0.060

T;T

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.21

N;N

PrimateAI

Benign

0.45

PROVEAN

Benign

-0.49

N;N

REVEL

Benign

0.0080

Sift

Benign

0.97

T;T

Sift4G

Benign

1.0

T;T

Polyphen

0.013

B;B

Vest4

0.13

MutPred

0.47

Loss of methylation at K186 (P = 0.0294);Loss of methylation at K186 (P = 0.0294);

MVP

0.076

MPC

0.042

ClinPred

0.012

GERP RS

-1.1

Varity_R

0.16

gMVP

0.15

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

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