rs201466849

Positions:

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_Strong

The ENST00000685320.1(DHCR7):c.-186G>T variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000608 in 1,612,810 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00037 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

DHCR7
ENST00000685320.1 5_prime_UTR_premature_start_codon_gain

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: 0.0930

Variant links:

Genes affected

DHCR7 (HGNC:2860): (7-dehydrocholesterol reductase) This gene encodes an enzyme that removes the C(7-8) double bond in the B ring of sterols and catalyzes the conversion of 7-dehydrocholesterol to cholesterol. This gene is ubiquitously expressed and its transmembrane protein localizes to the endoplasmic reticulum membrane and nuclear outer membrane. Mutations in this gene cause Smith-Lemli-Opitz syndrome (SLOS); a syndrome that is metabolically characterized by reduced serum cholesterol levels and elevated serum 7-dehydrocholesterol levels and phenotypically characterized by cognitive disability, facial dysmorphism, syndactyly of second and third toes, and holoprosencephaly in severe cases to minimal physical abnormalities and near-normal intelligence in mild cases. Alternative splicing results in multiple transcript variants that encode the same protein.[provided by RefSeq, Aug 2009]

DHCR7 links:

DHCR7 (HGNC:):

DHCR7 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.043869883).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DHCR7	NM_001360.3 linkuse as main transcript	c.400G>T	p.Val134Leu	missense_variant	5/9	ENST00000355527.8	NP_001351.2	Q9UBM7A0A024R5F7
DHCR7	NM_001163817.2 linkuse as main transcript	c.400G>T	p.Val134Leu	missense_variant	5/9		NP_001157289.1	Q9UBM7A0A024R5F7
DHCR7	XM_011544777.3 linkuse as main transcript	c.400G>T	p.Val134Leu	missense_variant	5/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
DHCR7	ENST00000685320.1 linkuse as main transcript	c.-186G>T		5_prime_UTR_premature_start_codon_gain_variant	4/8			ENSP00000509319.1	B4E1K5
DHCR7	ENST00000355527.8 linkuse as main transcript	c.400G>T	p.Val134Leu	missense_variant	5/9	1	NM_001360.3	ENSP00000347717.4	Q9UBM7
DHCR7	ENST00000685320.1 linkuse as main transcript	c.-186G>T		5_prime_UTR_variant	4/8			ENSP00000509319.1	B4E1K5

Frequencies

GnomAD3 genomes

AF:

0.000362

AC:

AN:

152064

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00116

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000328

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:

0.000958

GnomAD3 exomes

AF:

0.0000721

AC:

AN:

249662

Hom.:

AF XY:

0.0000519

AC XY:

AN XY:

134900

show subpopulations

Gnomad AFR exome

AF:

0.000810

Gnomad AMR exome

AF:

0.000145

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS 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:

0.0000288

AC:

AN:

1460628

Hom.:

Cov.:

AF XY:

0.0000317

AC XY:

AN XY:

726554

show subpopulations

Gnomad4 AFR exome

AF:

0.000926

Gnomad4 AMR exome

AF:

0.000179

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:

9.00e-7

Gnomad4 OTH exome

AF:

0.0000332

GnomAD4 genome

AF:

0.000368

AC:

AN:

152182

Hom.:

Cov.:

AF XY:

0.000309

AC XY:

AN XY:

74388

show subpopulations

Gnomad4 AFR

AF:

0.00118

Gnomad4 AMR

AF:

0.000327

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000948

Alfa

AF:

0.0000448

Hom.:

Bravo

AF:

0.000385

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000824

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:7Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Smith-Lemli-Opitz syndrome

Uncertain:3Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Jan 25, 2022	- -
Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	May 01, 2018	- -
Likely benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 21, 2024	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Counsyl	May 04, 2018	- -

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jan 22, 2018	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Jun 28, 2024	Reported in an individual with SLOS in published literature; however, it is not known if this patient harbored a second variant in DHCR7 (PMID: 23042628); In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 23891399, 24813812, 29300326, 23042628) -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jul 09, 2024

Variant summary: DHCR7 c.400G>T (p.Val134Leu) results in a conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 7.2e-05 in 249662 control chromosomes, predominantly at a frequency of 0.00081 within the African or African-American subpopulation in the gnomAD database. This frequency is not significantly higher than estimated for a pathogenic variant in DHCR7 causing Smith-Lemli-Opitz Syndrome (7.2e-05 vs 0.0043), allowing no conclusion about variant significance. c.400G>T has been reported in the literature in unspecified individuals affected with Smith-Lemli-Opitz Syndrome, without strong evidence for causality (Waterham_2012). These report(s) do not provide unequivocal conclusions about association of the variant with Smith-Lemli-Opitz Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 23042628). ClinVar contains an entry for this variant (Variation ID: 93718). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 04, 2018

The p.V134L variant (also known as c.400G>T), located in coding exon 3 of the DHCR7 gene, results from a G to T substitution at nucleotide position 400. The valine at codon 134 is replaced by leucine, an amino acid with highly similar properties. This alteration was identified and considered causative in one study; however, no information regarding patient phenotype or second allele genotype was provided (Waterham HR et al. Am J Med Genet C Semin Med Genet, 2012 Nov;160C:263-84; Cross JL et al. Clin. Genet., 2015 Jun;87:570-5). This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.11

BayesDel_addAF

Benign

-0.072

BayesDel_noAF

Uncertain

0.090

CADD

Benign

6.3

DANN

Benign

0.94

DEOGEN2

Uncertain

0.65

D;D;.;T

Eigen

Benign

-0.82

Eigen_PC

Benign

-0.90

FATHMM_MKL

Benign

0.37

LIST_S2

Uncertain

0.86

.;D;D;T

M_CAP

Uncertain

0.12

MetaRNN

Benign

0.044

T;T;T;T

MetaSVM

Uncertain

0.15

MutationAssessor

Benign

1.4

L;L;.;.

PrimateAI

Benign

0.45

PROVEAN

Benign

-0.30

N;N;N;N

REVEL

Uncertain

0.64

Sift

Benign

0.38

T;T;T;T

Sift4G

Benign

0.87

T;T;.;.

Polyphen

0.38

B;B;.;.

Vest4

0.69

MutPred

0.35

Loss of disorder (P = 0.3108);Loss of disorder (P = 0.3108);.;Loss of disorder (P = 0.3108);

MVP

0.82

MPC

0.13

ClinPred

0.0033

GERP RS

0.13

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.036

gMVP

0.72

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over