rs769218623

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1PM2PP5

The NM_001360.3(DHCR7):​c.521T>C​(p.Phe174Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,614,090 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

DHCR7
NM_001360.3 missense

Scores

5
6
8

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:2

Conservation

PhyloP100: 8.13
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 5 ACMG points.

PM1
In a transmembrane_region Helical (size 20) in uniprot entity DHCR7_HUMAN there are 7 pathogenic changes around while only 0 benign (100%) in NM_001360.3
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 11-71441332-A-G is Pathogenic according to our data. Variant chr11-71441332-A-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 554967.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=2, Pathogenic=1}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
DHCR7NM_001360.3 linkuse as main transcriptc.521T>C p.Phe174Ser missense_variant 6/9 ENST00000355527.8 NP_001351.2
DHCR7NM_001163817.2 linkuse as main transcriptc.521T>C p.Phe174Ser missense_variant 6/9 NP_001157289.1
DHCR7XM_011544777.3 linkuse as main transcriptc.521T>C p.Phe174Ser missense_variant 6/9 XP_011543079.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
DHCR7ENST00000355527.8 linkuse as main transcriptc.521T>C p.Phe174Ser missense_variant 6/91 NM_001360.3 ENSP00000347717 P1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152198
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.00
GnomAD3 exomes
AF:
0.0000199
AC:
5
AN:
251044
Hom.:
0
AF XY:
0.00000737
AC XY:
1
AN XY:
135764
show subpopulations
Gnomad AFR exome
AF:
0.00
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:
0.00000410
AC:
6
AN:
1461892
Hom.:
0
Cov.:
34
AF XY:
0.00000138
AC XY:
1
AN XY:
727246
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.000112
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:
8.99e-7
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152198
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74362
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.000131
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:
0.00
Bravo
AF:
0.0000264
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Smith-Lemli-Opitz syndrome Pathogenic:2Uncertain:1
Likely pathogenic, criteria provided, single submitterclinical testingEquipe Genetique des Anomalies du Developpement, Université de BourgogneOct 18, 2021- -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 15, 2023This sequence change replaces phenylalanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 174 of the DHCR7 protein (p.Phe174Ser). This variant is present in population databases (rs769218623, gnomAD 0.01%). For these reasons, this variant has been classified as Pathogenic. 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) performed at Invitae indicates that this missense variant is expected to disrupt DHCR7 protein function. ClinVar contains an entry for this variant (Variation ID: 554967). This missense change has been observed in individual(s) with Smith-Lemli-Opitz syndrome (PMID: 15979035, 26969503). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. -
Uncertain significance, criteria provided, single submitterclinical testingCounsylNov 09, 2017- -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpNov 17, 2021Variant summary: DHCR7 c.521T>C (p.Phe174Ser) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 2e-05 in 251044 control chromosomes. c.521T>C has been reported in the literature as a compound heterozygous genotype in at-least two individuals affected with Smith-Lemli-Opitz Syndrome, one of whom was reported as having a milder phenotypic presentation (example, Cardoso_2005, Tucci_2016). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as likely pathogenic and one laboratory classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.67
BayesDel_addAF
Pathogenic
0.29
D
BayesDel_noAF
Pathogenic
0.43
CADD
Uncertain
24
DANN
Benign
0.89
DEOGEN2
Uncertain
0.76
D;D;.
Eigen
Benign
0.075
Eigen_PC
Benign
0.092
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.89
.;D;D
M_CAP
Uncertain
0.24
D
MetaRNN
Uncertain
0.71
D;D;D
MetaSVM
Uncertain
0.62
D
MutationAssessor
Benign
1.3
L;L;.
MutationTaster
Benign
1.0
D;D
PrimateAI
Pathogenic
0.81
D
PROVEAN
Benign
-1.0
N;N;N
REVEL
Pathogenic
0.76
Sift
Benign
0.40
T;T;T
Sift4G
Benign
0.39
T;T;.
Polyphen
0.85
P;P;.
Vest4
0.87
MutPred
0.57
Loss of stability (P = 0.0453);Loss of stability (P = 0.0453);.;
MVP
0.94
MPC
0.65
ClinPred
0.32
T
GERP RS
4.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.37
gMVP
0.96

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: rs769218623; hg19: chr11-71152378; API