7-99707903-C-A

Variant names:

• chr7-99707903-C-A
• NM_000765.5:c.1325G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000765.5(CYP3A7):​c.1325G>T​(p.Cys442Phe) 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: CYP3A7 NM_000765.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.40
• 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_pathogenic. The variant received 8 ACMG points.

• PM1: In a binding_site axial binding residue (size 0) in uniprot entity CP3A7_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.995

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYP3A7	NM_000765.5	c.1325G>T	p.Cys442Phe	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.1325G>T	p.Cys442Phe	missense_variant	Exon 12 of 13	1	NM_000765.5	ENSP00000337450.2
CYP3A7-CYP3A51P	ENST00000620220.6	c.1325G>T	p.Cys442Phe	missense_variant	Exon 12 of 13	1		ENSP00000479282.3
CYP3A7-CYP3A51P	ENST00000611620.4	c.1325G>T	p.Cys442Phe	missense_variant	Exon 12 of 15	5		ENSP00000480571.1
CYP3A7	ENST00000477357.5	n.1664G>T		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: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Feb 03, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1325G>T (p.C442F) alteration is located in exon 12 (coding exon 12) of the CYP3A7 gene. This alteration results from a G to T substitution at nucleotide position 1325, causing the cysteine (C) at amino acid position 442 to be replaced by a phenylalanine (F). 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	Pathogenic	0.93
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.56
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.67	.;D;.
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.86	D;D;D
M_CAP	Pathogenic	0.74	D
MetaRNN	Pathogenic	0.99	D;D;D
MetaSVM	Pathogenic	0.89	D
MutationAssessor	Pathogenic	4.8	.;H;.
PhyloP100		7.4
PrimateAI	Uncertain	0.59	T
PROVEAN	Pathogenic	-9.9	.;D;.
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	.;D;.
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	.;D;.
Vest4		0.94
MutPred		0.92		Gain of MoRF binding (P = 0.0878);Gain of MoRF binding (P = 0.0878);Gain of MoRF binding (P = 0.0878);
MVP		0.95
MPC		0.72
ClinPred		1.0	D
GERP RS		3.7
Varity_R		0.94
gMVP		0.98
Mutation Taster		=22/78	disease causing

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

hg19: chr7-99305526;