2-218814971-C-T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2PP3PP5_Very_Strong

The NM_000784.4(CYP27A1):​c.1537C>T​(p.Arg513Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000248 in 1,614,166 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

CYP27A1
NM_000784.4 missense

Scores

11
7
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3U:3

Conservation

PhyloP100: 3.65
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 11 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.826
PP5
Variant 2-218814971-C-T is Pathogenic according to our data. Variant chr2-218814971-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 557779.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CYP27A1NM_000784.4 linkuse as main transcriptc.1537C>T p.Arg513Cys missense_variant 9/9 ENST00000258415.9 NP_000775.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CYP27A1ENST00000258415.9 linkuse as main transcriptc.1537C>T p.Arg513Cys missense_variant 9/91 NM_000784.4 ENSP00000258415 P1
CYP27A1ENST00000494263.5 linkuse as main transcriptn.2249C>T non_coding_transcript_exon_variant 7/72

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152184
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000517
AC:
13
AN:
251486
Hom.:
0
AF XY:
0.0000589
AC XY:
8
AN XY:
135914
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.000294
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000246
AC:
36
AN:
1461864
Hom.:
0
Cov.:
32
AF XY:
0.0000358
AC XY:
26
AN XY:
727240
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000126
Gnomad4 SAS exome
AF:
0.000255
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000540
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152302
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74480
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.000131
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000207
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000264
ExAC
AF:
0.0000576
AC:
7

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:3Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cholestanol storage disease Pathogenic:3Uncertain:2
Likely pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 15, 2024This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 513 of the CYP27A1 protein (p.Arg513Cys). This variant is present in population databases (rs560108684, gnomAD 0.03%). This missense change has been observed in individual(s) with clinical features of CYP27A1-related conditions (PMID: 28623566, 31743419, 32714376, 34012265). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 557779). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on CYP27A1 protein function. This variant disrupts the p.Arg513 amino acid residue in CYP27A1. Other variant(s) that disrupt this residue have been observed in individuals with CYP27A1-related conditions (PMID: 22878431), which suggests that this may be a clinically significant amino acid residue. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsMar 30, 2024- -
Uncertain significance, flagged submissionclinical testingCounsylApr 11, 2018- -
Likely pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpApr 05, 2022Variant summary: CYP27A1 c.1537C>T (p.Arg513Cys) results in a non-conservative amino acid change in the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 5.2e-05 in 251486 control chromosomes. This frequency is not significantly higher than expected for a pathogenic variant in CYP27A1 causing Cerebrotendinous Xanthomatosis (5.2e-05 vs 0.0011), allowing no conclusion about variant significance. c.1537C>T has been reported in the literature in the compound heterozygous state in individuals affected with Cerebrotendinous Xanthomatosis, including two individuals from a single family (Chen_2017, Jiang_2020, Zhang_2021). These data indicate that the variant is likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as likely pathogenic. -
Uncertain significance, flagged submissionclinical testingNatera, Inc.Sep 16, 2020- -
CYP27A1-related disorder Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesJul 31, 2024The CYP27A1 c.1537C>T variant is predicted to result in the amino acid substitution p.Arg513Cys. This variant has been reported in the compound heterozygous state in individuals with cerebrotendinous xanthomatosis (Chen et al. 2017. PubMed ID: 28623566; Jiang et al. 2020. PubMed ID: 32714376). This variant is reported in 0.029% of alleles in individuals of South Asian descent in gnomAD. This variant has interpretations ranging from uncertain significance to pathogenic in ClinVar (https://www.ncbi.nlm.nih.gov/clinvar/variation/557779/). Although we suspect that this variant may be pathogenic, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.45
BayesDel_addAF
Uncertain
0.15
D
BayesDel_noAF
Pathogenic
0.28
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.73
D
Eigen
Pathogenic
0.75
Eigen_PC
Pathogenic
0.67
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.96
D
M_CAP
Pathogenic
0.37
D
MetaRNN
Pathogenic
0.83
D
MetaSVM
Uncertain
0.10
D
MutationAssessor
Pathogenic
3.3
M
MutationTaster
Benign
1.0
D
PrimateAI
Uncertain
0.53
T
PROVEAN
Pathogenic
-6.6
D
REVEL
Pathogenic
0.66
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0010
D
Polyphen
1.0
D
Vest4
0.73
MutPred
0.66
Loss of MoRF binding (P = 0.001);
MVP
0.90
MPC
0.84
ClinPred
0.99
D
GERP RS
4.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.88
gMVP
0.91

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.

Other links and lift over

dbSNP: rs560108684; hg19: chr2-219679694; API