rs539356203

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M383R) has been classified 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

11
6
1

Clinical Significance

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

Conservation

PhyloP100: 7.87

Publications

2 publications found
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 Gene-Disease associations (from GenCC):
  • cerebrotendinous xanthomatosis
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Genomics England PanelApp, G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.901

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CYP27A1NM_000784.4 linkc.1148T>A p.Met383Lys missense_variant Exon 6 of 9 ENST00000258415.9 NP_000775.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CYP27A1ENST00000258415.9 linkc.1148T>A p.Met383Lys missense_variant Exon 6 of 9 1 NM_000784.4 ENSP00000258415.4
CYP27A1ENST00000494263.5 linkn.1582T>A non_coding_transcript_exon_variant Exon 6 of 7 2
CYP27A1ENST00000445971.1 linkn.*609T>A downstream_gene_variant 5 ENSP00000404945.1
CYP27A1ENST00000466602.1 linkn.*60T>A downstream_gene_variant 2

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152238
Hom.:
0
Cov.:
32
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
GnomAD2 exomes
AF:
0.000171
AC:
43
AN:
251402
AF XY:
0.0000810
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000328
AC:
48
AN:
1461892
Hom.:
1
Cov.:
31
AF XY:
0.0000179
AC XY:
13
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00107
AC:
48
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.487
Heterozygous variant carriers
0
5
10
14
19
24
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152356
Hom.:
0
Cov.:
32
AF XY:
0.0000268
AC XY:
2
AN XY:
74504
show subpopulations
African (AFR)
AF:
0.0000240
AC:
1
AN:
41596
American (AMR)
AF:
0.000327
AC:
5
AN:
15308
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.467
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000378
ExAC
AF:
0.0000741
AC:
9
Asia WGS
AF:
0.000289
AC:
1
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
Jan 24, 2020
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Aug 23, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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
Oct 05, 2017
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Jan 26, 2018
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Cardiovascular phenotype Uncertain:1
Dec 15, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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
T
BayesDel_noAF
Pathogenic
0.25
CADD
Pathogenic
26
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.77
D
Eigen
Pathogenic
0.84
Eigen_PC
Pathogenic
0.77
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Benign
0.75
T
M_CAP
Uncertain
0.12
D
MetaRNN
Pathogenic
0.90
D
MetaSVM
Uncertain
0.47
D
MutationAssessor
Pathogenic
3.3
M
PhyloP100
7.9
PrimateAI
Uncertain
0.63
T
PROVEAN
Pathogenic
-5.3
D
REVEL
Pathogenic
0.87
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0010
D
Vest4
0.89
ClinPred
0.53
D
GERP RS
5.8
Varity_R
0.98
gMVP
0.97
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

Publications

Other links and lift over

dbSNP: rs539356203; hg19: chr2-219678874; API