15-74749942-G-A

Position:

• chr15-74749942-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_000761.5(CYP1A2):​c.204G>A​(p.Met68Ile) 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. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CYP1A2 NM_000761.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.62

Genes affected

CYP1A2 (HGNC:2596): (cytochrome P450 family 1 subfamily A member 2) This gene 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. The protein encoded by this gene localizes to the endoplasmic reticulum and its expression is induced by some polycyclic aromatic hydrocarbons (PAHs), some of which are found in cigarette smoke. The enzyme's endogenous substrate is unknown; however, it is able to metabolize some PAHs to carcinogenic intermediates. Other xenobiotic substrates for this enzyme include caffeine, aflatoxin B1, and acetaminophen. The transcript from this gene contains four Alu sequences flanked by direct repeats in the 3' untranslated region. [provided by RefSeq, Jul 2008]

ACMG classification

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=0.34843576).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CYP1A2	NM_000761.5	c.204G>A	p.Met68Ile	missense_variant	2/7	ENST00000343932.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CYP1A2	ENST00000343932.5	c.204G>A	p.Met68Ile	missense_variant	2/7	1	NM_000761.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 29, 2022

The c.204G>A (p.M68I) alteration is located in exon 2 (coding exon 1) of the CYP1A2 gene. This alteration results from a G to A substitution at nucleotide position 204, causing the methionine (M) at amino acid position 68 to be replaced by an isoleucine (I). 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	0.48
BayesDel_addAF	Benign	-0.076	T
BayesDel_noAF	Benign	-0.35
CADD	Benign	19
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.63	D
Eigen	Benign	-0.10
Eigen_PC	Benign	-0.042
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Benign	0.82	T
M_CAP	Benign	0.017	T
MetaRNN	Benign	0.35	T
MetaSVM	Benign	-0.68	T
MutationAssessor	Benign	1.6	L
MutationTaster	Benign	1.0	D
PrimateAI	Benign	0.36	T
PROVEAN	Benign	-2.1	N
REVEL	Benign	0.19
Sift	Uncertain	0.0090	D
Sift4G	Uncertain	0.012	D
Vest4		0.32
MutPred		0.61		Loss of methylation at R67 (P = 0.1026);
MVP		0.54
MPC		0.069
ClinPred		0.93	D
GERP RS		3.2
Varity_R		0.60
gMVP		0.69

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr15-75042283;