2-218814186-C-A

Variant summary

Our verdict is Pathogenic. The variant received 15 ACMG points: 15P and 0B. PM1PM2PM5PP3PP5_Very_Strong

The NM_000784.4(CYP27A1):​c.1183C>A​(p.Arg395Ser) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000958 in 1,461,856 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R395H) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000096 ( 0 hom. )

Consequence

CYP27A1
NM_000784.4 missense, splice_region

Scores

11
6
1
Splicing: ADA: 0.9744
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5U:1

Conservation

PhyloP100: 1.02

Publications

43 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: Myriad Women’s Health, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P, Orphanet, ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 15 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 13 uncertain in NM_000784.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr2-218814187-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 65834.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP3
Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.
PP5
Variant 2-218814186-C-A is Pathogenic according to our data. Variant chr2-218814186-C-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 4261.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000784.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CYP27A1
NM_000784.4
MANE Select
c.1183C>Ap.Arg395Ser
missense splice_region
Exon 6 of 9NP_000775.1Q02318

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CYP27A1
ENST00000258415.9
TSL:1 MANE Select
c.1183C>Ap.Arg395Ser
missense splice_region
Exon 6 of 9ENSP00000258415.4Q02318
CYP27A1
ENST00000901553.1
c.1201C>Ap.Arg401Ser
missense splice_region
Exon 6 of 9ENSP00000571612.1
CYP27A1
ENST00000901558.1
c.1183C>Ap.Arg395Ser
missense splice_region
Exon 6 of 9ENSP00000571617.1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251236
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000958
AC:
14
AN:
1461856
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53404
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000108
AC:
12
AN:
1111996
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.471
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

ClinVar submissions
Significance:Pathogenic/Likely pathogenic
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
5
1
-
Cholestanol storage disease (6)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.50
CADD
Pathogenic
32
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.86
D
Eigen
Pathogenic
0.75
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Benign
0.30
N
LIST_S2
Uncertain
0.92
D
M_CAP
Pathogenic
0.41
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.5
H
PhyloP100
1.0
PrimateAI
Uncertain
0.52
T
PROVEAN
Pathogenic
-5.5
D
REVEL
Pathogenic
0.92
Sift
Uncertain
0.028
D
Sift4G
Uncertain
0.030
D
Polyphen
1.0
D
Vest4
0.88
MutPred
0.98
Loss of methylation at R395 (P = 0.0885)
MVP
0.99
MPC
0.76
ClinPred
0.98
D
GERP RS
5.8
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.98
gMVP
0.98
Mutation Taster
=13/87
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
0.97
dbscSNV1_RF
Pathogenic
0.79
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: rs121908096; hg19: chr2-219678909; COSMIC: COSV99033441; COSMIC: COSV99033441; API