10-94695007-A-G

Variant summary

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

The NM_000772.3(CYP2C18):c.572A>G(p.Asp191Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,072 control chromosomes in the GnomAD database, with no homozygous occurrence. 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)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CYP2C18 NM_000772.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.54

Genes affected

CYP2C18 (HGNC:2620): (cytochrome P450 family 2 subfamily C member 18) This gene 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 but its specific substrate has not yet been determined. The gene is located within a cluster of cytochrome P450 genes on chromosome 10q24. An additional gene, CYP2C17, was once thought to exist; however, CYP2C17 is now considered an artefact based on a chimera of CYP2C18 and CYP2C19. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

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, 0.97

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CYP2C18	NM_000772.3	c.572A>G	p.Asp191Gly	missense_variant	4/9	ENST00000285979.11
CYP2C18	NM_001128925.2	c.572A>G	p.Asp191Gly	missense_variant	4/8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CYP2C18	ENST00000285979.11	c.572A>G	p.Asp191Gly	missense_variant	4/9	1	NM_000772.3	P1
CYP2C18	ENST00000339022.6	c.572A>G	p.Asp191Gly	missense_variant	4/8	1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461072 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726830

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

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 14, 2021

The c.572A>G (p.D191G) alteration is located in exon 4 (coding exon 4) of the CYP2C18 gene. This alteration results from a A to G substitution at nucleotide position 572, causing the aspartic acid (D) at amino acid position 191 to be replaced by a glycine (G). 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	0.68
BayesDel_addAF	Uncertain	0.057	T
BayesDel_noAF	Benign	-0.16
Cadd	Benign	23
Dann	Uncertain	1.0
DEOGEN2	Benign	0.26	T;.
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.36
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Uncertain	0.93	D;D
M_CAP	Benign	0.064	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Uncertain	0.45	D
MutationAssessor	Pathogenic	3.7	H;H
MutationTaster	Benign	0.99	N;N
PROVEAN	Pathogenic	-6.3	D;D
REVEL	Uncertain	0.63
Sift	Uncertain	0.0010	D;D
Sift4G	Uncertain	0.0020	D;D
Polyphen		1.0	D;.
Vest4		0.52
MutPred		0.88		Gain of ubiquitination at K190 (P = 0.115);Gain of ubiquitination at K190 (P = 0.115);
MVP		0.86
MPC		0.050
ClinPred		1.0	D
GERP RS		4.5
Varity_R		0.91
gMVP		0.21

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

Publications

LitVar

Other links and lift over

dbSNP: rs1004256316; hg19: chr10-96454764;