7-99705520-C-A

Variant names:

• chr7-99705520-C-A
• rs757100968
• NM_000765.5:c.1492G>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000765.5(CYP3A7):​c.1492G>T​(p.Glu498*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,334 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CYP3A7 NM_000765.5 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.168
• Publications: 0 publications found

Genes affected

CYP3A7 (HGNC:2640): (cytochrome P450 family 3 subfamily A member 7) This gene encodes a member of the cytochrome P450 superfamily of enzymes, which participate in drug metabolism and the synthesis of cholesterol, steroids and other lipids. This enzyme hydroxylates testosterone and dehydroepiandrosterone 3-sulphate, which is involved in the formation of estriol during pregnancy. This gene is part of a cluster of related genes on chromosome 7q21.1. Naturally-occurring readthrough transcription occurs between this gene and the downstream CYP3A51P pseudogene and is represented by GeneID:100861540. [provided by RefSeq, Jan 2015]

CYP3A7-CYP3A51P (HGNC:51504): (CYP3A7-CYP3A51P readthrough) This locus represents readthrough transcription between the neighboring CYP3A7 (cytochrome P450, family 3, subfamily A, polypeptide 7) and CYP3A51P (cytochrome P450, family 3, subfamily A, polypeptide 51, pseudogene) genes, which are members of the CYP3A gene cluster on chromosome 7. The downstream pseudogene is not known to be independently transcribed. The readthrough transcript includes CYP3A7 exons 1-13 and exons 2 and 13 of the pseudogene. It encodes a CYP3A isoform with a novel C-terminus. This isoform is only expressed in alleles containing a T nucleotide at the -6 position of a splice acceptor in the pseudogene, which enables correct splicing of the upstream CYP3A7 exons to the pseudogene exons. It should be noted that the reference genome sequence represents the CYP3A7_39256 T->A allele, and thus this haplotype is unlikely to produce the readthrough transcript. [provided by RefSeq, Jan 2015]

ZSCAN25 (HGNC:21961): (zinc finger and SCAN domain containing 25) This gene encodes a protein that bears some similarity to zinc finger proteins, which are involved in DNA binding and protein-protein interactions. Multiple alternatively spliced transcript variants have been identified, but the full-length nature for most of them has not been determined. [provided by RefSeq, Jul 2008]

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYP3A7	NM_000765.5	c.1492G>T	p.Glu498*	stop_gained	Exon 13 of 13	ENST00000336374.4	NP_000756.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CYP3A7	ENST00000336374.4	c.1492G>T	p.Glu498*	stop_gained	Exon 13 of 13	1	NM_000765.5	ENSP00000337450.2
CYP3A7-CYP3A51P	ENST00000620220.6	c.1416+2292G>T		intron_variant	Intron 12 of 12	1		ENSP00000479282.3
CYP3A7-CYP3A51P	ENST00000611620.4	c.1492G>T	p.Glu498*	stop_gained	Exon 13 of 15	5		ENSP00000480571.1
CYP3A7	ENST00000477357.5	n.1831G>T		non_coding_transcript_exon_variant	Exon 10 of 10	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251130 AF XY: 0.00

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: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461334 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726984

African (AFR) AF: 0.00 AC: 0 AN: 33460

American (AMR) AF: 0.00 AC: 0 AN: 44702

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26116

East Asian (EAS) AF: 0.00 AC: 0 AN: 39674

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53386

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111616

Other (OTH) AF: 0.00 AC: 0 AN: 60364

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

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_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	34
DANN	Benign	0.95
Eigen	Benign	-0.023
Eigen_PC	Benign	-0.40
FATHMM_MKL	Benign	0.049	N
PhyloP100		0.17
Vest4		0.023
GERP RS		1.4
Mutation Taster		=131/69	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs757100968; hg19: chr7-99303143;