chr19-40845309-A-G

Variant names:

• chr19-40845309-A-G
• rs781140086
• NM_000762.6:c.1146T>C

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_000762.6(CYP2A6):​c.1146T>C​(p.Asp382Asp) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000869 in 1,611,172 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0000089 (0 hom.)
• Consequence: CYP2A6 NM_000762.6 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.41
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• coumarin resistance

  Inheritance: Unknown Classification: NO_KNOWN Submitted by: Labcorp Genetics (formerly Invitae)
• nicotine dependence

  Inheritance: Unknown Classification: NO_KNOWN Submitted by: Labcorp Genetics (formerly Invitae)

ENSG00000268797 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.99).
• BP7: Synonymous conserved (PhyloP=-1.41 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYP2A6	NM_000762.6	c.1146T>C	p.Asp382Asp	synonymous_variant	Exon 7 of 9	ENST00000301141.10	NP_000753.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CYP2A6	ENST00000301141.10	c.1146T>C	p.Asp382Asp	synonymous_variant	Exon 7 of 9	1	NM_000762.6	ENSP00000301141.4
CYP2A6	ENST00000596719.5	n.997T>C		non_coding_transcript_exon_variant	Exon 6 of 6	1
ENSG00000268797	ENST00000601627.1	n.117+43894A>G		intron_variant	Intron 1 of 3	3		ENSP00000469533.1

Frequencies

GnomAD3 genomes AF: 0.00000663 AC: 1 AN: 150896 Hom.: 0 Cov.: 31

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251132 AF XY: 0.00000737

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000890 AC: 13 AN: 1460276 Hom.: 0 Cov.: 31 AF XY: 0.0000124 AC XY: 9 AN XY: 726458

African (AFR) AF: 0.00 AC: 0 AN: 33458

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 38446

South Asian (SAS) AF: 0.00 AC: 0 AN: 86152

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53368

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.0000117 AC: 13 AN: 1111948

Other (OTH) AF: 0.00 AC: 0 AN: 60286

GnomAD4 genome AF: 0.00000663 AC: 1 AN: 150896 Hom.: 0 Cov.: 31 AF XY: 0.0000136 AC XY: 1 AN XY: 73554

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 40934

American (AMR) AF: 0.00 AC: 0 AN: 15196

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3466

East Asian (EAS) AF: 0.00 AC: 0 AN: 4904

South Asian (SAS) AF: 0.00 AC: 0 AN: 4732

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10478

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67884

Other (OTH) AF: 0.00 AC: 0 AN: 2078

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.99
CADD	Benign	2.9
DANN	Benign	0.31
PhyloP100		-1.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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

Other links and lift over

dbSNP: rs781140086; hg19: chr19-41351214;