2-218781848-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BS1_Supporting

The ENST00000494263.5(CYP27A1):n.100C>T variant causes a non coding transcript exon change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000582 in 347,272 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.0012 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00012 (0 hom.)
• Consequence: CYP27A1 ENST00000494263.5 non_coding_transcript_exon
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.437

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]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00117 (178/152324) while in subpopulation AFR AF= 0.00404 (168/41590). AF 95% confidence interval is 0.00354. There are 0 homozygotes in gnomad4. There are 85 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CYP27A1	ENST00000494263.5	n.100C>T		non_coding_transcript_exon_variant	1/7	2

Frequencies

GnomAD3 genomes AF: 0.00117 AC: 178 AN: 152206 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00405

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000393

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00316

Gnomad NFE AF: 0.0000441

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000123 AC: 24 AN: 194948 Hom.: 0 Cov.: 2 AF XY: 0.0000891 AC XY: 9 AN XY: 101018

Gnomad4 AFR exome AF: 0.00386

Gnomad4 AMR exome AF: 0.000379

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: 0.00000819

Gnomad4 OTH exome AF: 0.000324

GnomAD4 genome AF: 0.00117 AC: 178 AN: 152324 Hom.: 0 Cov.: 32 AF XY: 0.00114 AC XY: 85 AN XY: 74466

Gnomad4 AFR AF: 0.00404

Gnomad4 AMR AF: 0.000392

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000441

Gnomad4 OTH AF: 0.00

Alfa AF: 0.00101 Hom.: 0

Bravo AF: 0.00137

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cholestanol storage disease Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
Cadd	Benign	1.5
Dann	Benign	0.93

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

Other links and lift over

dbSNP: rs528284503; hg19: chr2-219646571;