rs387906258

Variant names:

• chr12-57765169-TC-T
• rs387906258
• NM_000785.4:c.631delG

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000785.4(CYP27B1):​c.631delG​(p.Glu211ArgfsTer24) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: CYP27B1 NM_000785.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 4.56

Genes affected

CYP27B1 (HGNC:2606): (cytochrome P450 family 27 subfamily B 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. The protein encoded by this gene localizes to the inner mitochondrial membrane where it hydroxylates 25-hydroxyvitamin D3 at the 1alpha position. This reaction synthesizes 1alpha,25-dihydroxyvitamin D3, the active form of vitamin D3, which binds to the vitamin D receptor and regulates calcium metabolism. Thus this enzyme regulates the level of biologically active vitamin D and plays an important role in calcium homeostasis. Mutations in this gene can result in vitamin D-dependent rickets type I. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 12-57765169-TC-T is Pathogenic according to our data. Variant chr12-57765169-TC-T is described in ClinVar as [Pathogenic]. Clinvar id is 1662.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYP27B1	NM_000785.4	c.631delG	p.Glu211ArgfsTer24	frameshift_variant	Exon 4 of 9	ENST00000228606.9	NP_000776.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CYP27B1	ENST00000228606.9	c.631delG	p.Glu211ArgfsTer24	frameshift_variant	Exon 4 of 9	1	NM_000785.4	ENSP00000228606.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Vitamin D-dependent rickets, type 1A Pathogenic:1

Dec 01, 1997

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

not provided Pathogenic:1

Jan 10, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This sequence change creates a premature translational stop signal (p.Glu211Argfs*24) in the CYP27B1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CYP27B1 are known to be pathogenic (PMID: 9837822, 17488797). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with vitamin D-dependent rickets (PMID: 9415400). ClinVar contains an entry for this variant (Variation ID: 1662). -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.14		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: rs387906258; hg19: chr12-58158952;