15-74721446-G-T

Position:

• chr15-74721446-G-T

Variant summary

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

The NM_001319217.2(CYP1A1):​c.1010C>A​(p.Pro337His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CYP1A1 NM_001319217.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.59

Genes affected

CYP1A1 (HGNC:2595): (cytochrome P450 family 1 subfamily A member 1) This gene, CYP1A1, 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 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. The gene has been associated with lung cancer risk. A related family member, CYP1A2, is located approximately 25 kb away from CYP1A1 on chromosome 15. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jan 2016]

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, 0.989

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CYP1A1	NM_001319217.2	c.1010C>A	p.Pro337His	missense_variant	4/7	ENST00000379727.8
CYP1A1	NM_000499.5	c.1010C>A	p.Pro337His	missense_variant	4/7
CYP1A1	NM_001319216.2	c.1010C>A	p.Pro337His	missense_variant	4/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CYP1A1	ENST00000379727.8	c.1010C>A	p.Pro337His	missense_variant	4/7	1	NM_001319217.2	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

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

Dec 28, 2022

The c.1010C>A (p.P337H) alteration is located in exon 4 (coding exon 3) of the CYP1A1 gene. This alteration results from a C to A substitution at nucleotide position 1010, causing the proline (P) at amino acid position 337 to be replaced by a histidine (H). 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	0.25
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.44
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.23	T;T;D;D;D;T;.;T
Eigen	Pathogenic	0.76
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.93	D;D;D;.;.;.;D;D
M_CAP	Benign	0.072	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.8	.;.;H;H;H;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Benign	0.48	T
PROVEAN	Pathogenic	-7.5	.;.;D;D;D;D;D;D
REVEL	Pathogenic	0.74
Sift	Pathogenic	0.0	.;.;D;D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;D
Polyphen		1.0	.;D;D;D;D;D;.;.
Vest4		0.85
MutPred		0.87		.;Gain of MoRF binding (P = 0.0603);Gain of MoRF binding (P = 0.0603);Gain of MoRF binding (P = 0.0603);Gain of MoRF binding (P = 0.0603);Gain of MoRF binding (P = 0.0603);.;.;
MVP		1.0
MPC		0.25
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.91
gMVP		0.78

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: chr15-75013787; COSMIC: COSV101122211;