2-218812266-G-A

Position:

chr2-218812266-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000784.4(CYP27A1):c.491G>A(p.Arg164Gln) variant causes a missense change. The variant allele was found at a frequency of 0.000397 in 1,614,078 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00036 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00040 ( 0 hom. )

Consequence

CYP27A1
NM_000784.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 6.75

Variant links:

Genes affected

CYP27A1 (HGNC:2605): (cytochrome P450 family 27 subfamily A member 1) 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 mitochondrial protein oxidizes cholesterol intermediates as part of the bile synthesis pathway. Since the conversion of cholesterol to bile acids is the major route for removing cholesterol from the body, this protein is important for overall cholesterol homeostasis. Mutations in this gene cause cerebrotendinous xanthomatosis, a rare autosomal recessive lipid storage disease. [provided by RefSeq, Jul 2008]

CYP27A1 links:

CYP27A1 (HGNC:):

CYP27A1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CYP27A1	NM_000784.4 linkuse as main transcript	c.491G>A	p.Arg164Gln	missense_variant	3/9	ENST00000258415.9	NP_000775.1	Q02318

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CYP27A1	ENST00000258415.9 linkuse as main transcript	c.491G>A	p.Arg164Gln	missense_variant	3/9	1	NM_000784.4	ENSP00000258415.4		Q02318

Frequencies

GnomAD3 genomes

AF:

0.000361

AC:

AN:

152212

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000723

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.000565

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000647

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000282

AC:

AN:

251450

Hom.:

AF XY:

0.000294

AC XY:

AN XY:

135898

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.000185

Gnomad NFE exome

AF:

0.000554

Gnomad OTH exome

AF:

0.000489

GnomAD4 exome

AF:

0.000400

AC:

585

AN:

1461866

Hom.:

Cov.:

AF XY:

0.000377

AC XY:

274

AN XY:

727236

show subpopulations

Gnomad4 AFR exome

AF:

0.0000597

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000348

Gnomad4 FIN exome

AF:

0.000262

Gnomad4 NFE exome

AF:

0.000488

Gnomad4 OTH exome

AF:

0.000381

GnomAD4 genome

AF:

0.000361

AC:

AN:

152212

Hom.:

Cov.:

AF XY:

0.000430

AC XY:

AN XY:

74364

show subpopulations

Gnomad4 AFR

AF:

0.0000723

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.000565

Gnomad4 NFE

AF:

0.000647

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000359

Hom.:

Bravo

AF:

0.000329

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.00104

AC:

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000233

AC:

ExAC

AF:

0.000255

AC:

EpiCase

AF:

0.000382

EpiControl

AF:

0.000533

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Mar 01, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	May 15, 2018	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Dec 11, 2024	In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Cholestanol storage disease

Uncertain:1Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -
Likely benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 30, 2024	- -

CYP27A1-related disorder

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Sep 08, 2022

The CYP27A1 c.491G>A variant is predicted to result in the amino acid substitution p.Arg164Gln. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.060% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/2-219676989-G-A). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Intellectual disability

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Centre de Biologie Pathologie Génétique, Centre Hospitalier Universitaire de Lille

Jan 01, 2019

- -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 04, 2024

The p.R164Q variant (also known as c.491G>A), located in coding exon 3 of the CYP27A1 gene, results from a G to A substitution at nucleotide position 491. The arginine at codon 164 is replaced by glutamine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.13

BayesDel_addAF

Benign

-0.20

BayesDel_noAF

Benign

-0.13

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.59

D;T

Eigen

Uncertain

0.62

Eigen_PC

Uncertain

0.61

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.93

D;D

M_CAP

Benign

0.049

MetaRNN

Uncertain

0.47

T;T

MetaSVM

Uncertain

-0.27

MutationAssessor

Pathogenic

3.1

M;.

PrimateAI

Benign

0.43

PROVEAN

Uncertain

-2.8

D;D

REVEL

Uncertain

0.36

Sift

Uncertain

0.0090

D;D

Sift4G

Uncertain

0.018

D;T

Polyphen

1.0

D;.

Vest4

0.61

MVP

0.82

MPC

0.56

ClinPred

0.75

GERP RS

5.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.55

gMVP

0.76

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over