chr7-99707951-T-C

Variant names:

• chr7-99707951-T-C
• NM_000765.5:c.1277A>G

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 2P and 6B. PM2 BP4_Strong BP6_Moderate

The NM_000765.5(CYP3A7):​c.1277A>G​(p.Asn426Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N426K) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CYP3A7 NM_000765.5 missense
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -4.53
• 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: Likely_benign. The variant received -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.029690653).
• BP6: Variant 7-99707951-T-C is Benign according to our data. Variant chr7-99707951-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 4008933.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYP3A7	NM_000765.5	c.1277A>G	p.Asn426Ser	missense_variant	Exon 12 of 13	ENST00000336374.4	NP_000756.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CYP3A7	ENST00000336374.4	c.1277A>G	p.Asn426Ser	missense_variant	Exon 12 of 13	1	NM_000765.5	ENSP00000337450.2
CYP3A7-CYP3A51P	ENST00000620220.6	c.1277A>G	p.Asn426Ser	missense_variant	Exon 12 of 13	1		ENSP00000479282.3
CYP3A7-CYP3A51P	ENST00000611620.4	c.1277A>G	p.Asn426Ser	missense_variant	Exon 12 of 15	5		ENSP00000480571.1
CYP3A7	ENST00000477357.5	n.1616A>G		non_coding_transcript_exon_variant	Exon 9 of 10	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Benign:1

May 04, 2025

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.061
BayesDel_addAF	Benign	-0.35	T
BayesDel_noAF	Benign	-0.74
CADD	Benign	0.0030
DANN	Benign	0.28
DEOGEN2	Benign	0.078	.;T;.
Eigen	Benign	-1.4
Eigen_PC	Benign	-1.3
FATHMM_MKL	Benign	0.0093	N
LIST_S2	Benign	0.49	T;T;T
M_CAP	Benign	0.0091	T
MetaRNN	Benign	0.030	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-0.34	.;N;.
PhyloP100		-4.5
PrimateAI	Benign	0.28	T
PROVEAN	Benign	-0.59	.;N;.
REVEL	Benign	0.060
Sift	Benign	1.0	.;T;.
Sift4G	Benign	1.0	T;T;T
Polyphen		0.0	.;B;.
Vest4		0.048
MutPred		0.37		Gain of phosphorylation at N426 (P = 0.059);Gain of phosphorylation at N426 (P = 0.059);Gain of phosphorylation at N426 (P = 0.059);
MVP		0.32
MPC		0.097
ClinPred		0.029	T
GERP RS		-0.98
Varity_R		0.038
gMVP		0.43
Mutation Taster		=98/2	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.15		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

hg19: chr7-99305574;