rs104886035

Positions:

• chr11-71444163-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_001360.3(DHCR7):​c.151C>T​(p.Pro51Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,609,368 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P51L) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: DHCR7 NM_001360.3 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 8.31

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]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_001360.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr11-71444162-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2823123.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988
• PP5: Variant 11-71444163-G-A is Pathogenic according to our data. Variant chr11-71444163-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 93712.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr11-71444163-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DHCR7	NM_001360.3	c.151C>T	p.Pro51Ser	missense_variant	4/9	ENST00000355527.8
DHCR7	NM_001163817.2	c.151C>T	p.Pro51Ser	missense_variant	4/9
DHCR7	XM_011544777.3	c.151C>T	p.Pro51Ser	missense_variant	4/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DHCR7	ENST00000355527.8	c.151C>T	p.Pro51Ser	missense_variant	4/9	1	NM_001360.3	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152160 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1457208 Hom.: 0 Cov.: 35 AF XY: 0.00000138 AC XY: 1 AN XY: 724352

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 9.01e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152160 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74338

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Smith-Lemli-Opitz syndrome Pathogenic:4

Pathogenic, no assertion criteria provided	clinical testing	Natera, Inc.	Nov 28, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Jul 13, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jul 16, 2023	This sequence change replaces proline, which is neutral and non-polar, with serine, which is neutral and polar, at codon 51 of the DHCR7 protein (p.Pro51Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with Smith- Lemli-Opitz syndrome (PMID: 9653161, 16181459). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 93712). 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. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Oct 27, 2022	Variant summary: DHCR7 c.151C>T (p.Pro51Ser) 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 was absent in 241350 control chromosomes (gnomAD). c.151C>T has been reported in the literature in multiple individuals affected with Smith-Lemli-Opitz Syndrome (examples: Fitzky_1998, Ciara_2004 and Bianconi_2011). These data indicate that the variant is very likely to be associated with disease. Four clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and all classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Mar 18, 2013	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Oct 26, 2020	Not observed in large population cohorts (Lek et al., 2016); The majority of missense variants in this gene are considered pathogenic (Stenson et al., 2014); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 11175299, 21724437, 9653161, 12914579, 17497248, 24500076, 10677299, 23042628, 15521979, 21990131, 18249054, 10814720, 16983147) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.86
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.59
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	D;D;D;D;D;.;D
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.39
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Uncertain	0.13	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.5	H;H;.;.;.;.;.
MutationTaster	Benign	1.0	A;A
PrimateAI	Uncertain	0.54	T
PROVEAN	Pathogenic	-6.1	D;D;D;D;D;D;D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D;D;D;D;D;D;D
Sift4G	Uncertain	0.011	D;D;.;D;.;.;D
Polyphen		1.0	D;D;.;.;.;.;.
Vest4		0.97
MutPred		0.89		Gain of glycosylation at P51 (P = 0.0563);Gain of glycosylation at P51 (P = 0.0563);Gain of glycosylation at P51 (P = 0.0563);Gain of glycosylation at P51 (P = 0.0563);Gain of glycosylation at P51 (P = 0.0563);.;Gain of glycosylation at P51 (P = 0.0563);
MVP		0.97
MPC		0.57
ClinPred		0.99	D
GERP RS		4.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.60
gMVP		0.94

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: rs104886035; hg19: chr11-71155209;