rs539356203

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_000784.4(CYP27A1):c.1148T>A(p.Met383Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000335 in 1,614,248 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000033 ( 1 hom. )

Consequence

CYP27A1
NM_000784.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 7.87

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:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.901

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CYP27A1	NM_000784.4 linkuse as main transcript	c.1148T>A	p.Met383Lys	missense_variant	6/9	ENST00000258415.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CYP27A1	ENST00000258415.9 linkuse as main transcript	c.1148T>A	p.Met383Lys	missense_variant	6/9	1	NM_000784.4	P1
CYP27A1	ENST00000494263.5 linkuse as main transcript	n.1582T>A		non_coding_transcript_exon_variant	6/7	2

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152238

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000327

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000171

AC:

AN:

251402

Hom.:

AF XY:

0.0000810

AC XY:

AN XY:

135878

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00124

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000328

AC:

AN:

1461892

Hom.:

Cov.:

AF XY:

0.0000179

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00107

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:

0.00

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152356

Hom.:

Cov.:

AF XY:

0.0000268

AC XY:

AN XY:

74504

show subpopulations

Gnomad4 AFR

AF:

0.0000240

Gnomad4 AMR

AF:

0.000327

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000378

ExAC

AF:

0.0000741

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Cholestanol storage disease

Uncertain:2

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Jan 24, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 23, 2022	This sequence change replaces methionine, which is neutral and non-polar, with lysine, which is basic and polar, at codon 383 of the CYP27A1 protein (p.Met383Lys). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with CYP27A1-related conditions. ClinVar contains an entry for this variant (Variation ID: 289820). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Athena Diagnostics	Jan 26, 2018	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Oct 05, 2017	- -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Dec 15, 2021

The c.1148T>A (p.M383K) alteration is located in exon 6 (coding exon 6) of the CYP27A1 gene. This alteration results from a T to A substitution at nucleotide position 1148, causing the methionine (M) at amino acid position 383 to be replaced by a lysine (K). 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

0.64

BayesDel_addAF

Uncertain

0.042

BayesDel_noAF

Pathogenic

0.25

Cadd

Pathogenic

Dann

Uncertain

0.99

DEOGEN2

Uncertain

0.77

Eigen

Pathogenic

0.84

Eigen_PC

Pathogenic

0.77

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Benign

0.75

M_CAP

Uncertain

0.12

MetaRNN

Pathogenic

0.90

MetaSVM

Uncertain

0.47

MutationAssessor

Pathogenic

3.3

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.63

PROVEAN

Pathogenic

-5.3

REVEL

Pathogenic

0.87

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0010

Polyphen

1.0

Vest4

0.89

MutPred

0.83

Gain of disorder (P = 0.0377);

MVP

0.84

MPC

0.86

ClinPred

0.53

GERP RS

5.8

Varity_R

0.98

gMVP

0.97

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