Genetic Variant CYP2A6:p.Met489Thr (chr19-40843815-A-G) – ACMG Classification: Uncertain_significance (1 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_000762.6(CYP2A6):c.1466T>C(p.Met489Thr) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: not found (cov: 30)

Exomes 𝑓: 0.000011 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

CYP2A6
NM_000762.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.45

Variant links:

Genes affected

CYP2A6 (HGNC:2610): (cytochrome P450 family 2 subfamily A member 6) This gene, CYP2A6, encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This protein localizes to the endoplasmic reticulum and its expression is induced by phenobarbital. The enzyme is known to hydroxylate coumarin, and also metabolizes nicotine, aflatoxin B1, nitrosamines, and some pharmaceuticals. Individuals with certain allelic variants are said to have a poor metabolizer phenotype, meaning they do not efficiently metabolize coumarin or nicotine. This gene is part of a large cluster of cytochrome P450 genes from the CYP2A, CYP2B and CYP2F subfamilies on chromosome 19q. The gene was formerly referred to as CYP2A3; however, it has been renamed CYP2A6. [provided by RefSeq, Jul 2008]

CYP2A6 links:

ENSG00000268797 (HGNC:):

ENSG00000268797 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.30882728).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYP2A6	NM_000762.6 link	c.1466T>C	p.Met489Thr	missense_variant	Exon 9 of 9	ENST00000301141.10	NP_000753.3	P11509

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
CYP2A6	ENST00000301141.10 link	c.1466T>C	p.Met489Thr	missense_variant	Exon 9 of 9	1	NM_000762.6	ENSP00000301141.4	P11509
ENSG00000268797	ENST00000601627.1 link	n.117+42400A>G		intron_variant	Intron 1 of 3	3		ENSP00000469533.1	M0QY20
CYP2A6	ENST00000599960.1 link	n.385T>C		non_coding_transcript_exon_variant	Exon 2 of 2	2

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000799

AC:

AN:

250236

Hom.:

AF XY:

0.00000739

AC XY:

AN XY:

135336

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

Data not reliable, filtered out with message: AS_VQSR

AF:

0.0000110

AC:

AN:

1460210

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

726418

show subpopulations

Gnomad4 AFR exome

AF:

0.000209

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:

0.00000540

Gnomad4 OTH exome

AF:

0.0000332

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000508

Hom.:

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Nov 13, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1466T>C (p.M489T) alteration is located in exon 9 (coding exon 9) of the CYP2A6 gene. This alteration results from a T to C substitution at nucleotide position 1466, causing the methionine (M) at amino acid position 489 to be replaced by a threonine (T). 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

0.54

BayesDel_addAF

Benign

-0.11

BayesDel_noAF

Benign

-0.39

CADD

Uncertain

DANN

Uncertain

0.99

Eigen

Benign

0.12

Eigen_PC

Benign

0.039

FATHMM_MKL

Benign

0.35

LIST_S2

Uncertain

0.89

M_CAP

Benign

0.0065

MetaRNN

Benign

0.31

MetaSVM

Benign

-1.1

PrimateAI

Uncertain

0.56

PROVEAN

Uncertain

-3.3

REVEL

Benign

0.14

Sift

Uncertain

0.0010

Sift4G

Pathogenic

0.0010

Vest4

0.27

MutPred

0.70

Gain of glycosylation at M489 (P = 0.0427);

MVP

0.48

MPC

3.3

ClinPred

0.90

GERP RS

3.0

gMVP

0.68

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