NM_001360.3:c.532A>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1PM2PM5

The NM_001360.3(DHCR7):​c.532A>T​(p.Ile178Phe) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,886 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I178M) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

DHCR7
NM_001360.3 missense

Scores

5
7
7

Clinical Significance

Uncertain significance criteria provided, single submitter U:2

Conservation

PhyloP100: 5.30

Publications

1 publications found
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 Gene-Disease associations (from GenCC):
  • Smith-Lemli-Opitz syndrome
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Myriad Women’s Health, Laboratory for Molecular Medicine, ClinGen, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM1
In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 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 chr11-71441320-A-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2137194.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
DHCR7NM_001360.3 linkc.532A>T p.Ile178Phe missense_variant Exon 6 of 9 ENST00000355527.8 NP_001351.2 Q9UBM7A0A024R5F7

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
DHCR7ENST00000355527.8 linkc.532A>T p.Ile178Phe missense_variant Exon 6 of 9 1 NM_001360.3 ENSP00000347717.4 Q9UBM7
DHCR7ENST00000685320.1 linkc.-54A>T 5_prime_UTR_variant Exon 5 of 8 ENSP00000509319.1 B4E1K5

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
250988
AF XY:
0.00000737
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000883
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461886
Hom.:
0
Cov.:
34
AF XY:
0.00000275
AC XY:
2
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1112008
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Mar 20, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: DHCR7 c.532A>T (p.Ile178Phe) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 250988 control chromosomes (gnomAD). c.532A>T has been reported in the literature in the compound heterozygous state in individuals affected with Smith-Lemli-Opitz Syndrome (e.g. Haas_2005, Witsch-Baumgartner_2005). 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. The following publications have been ascertained in the context of this evaluation (PMID: 15776424, 16435228). ClinVar contains an entry for this variant (Variation ID: 558484). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Smith-Lemli-Opitz syndrome Uncertain:1
May 23, 2018
Counsyl
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.30
BayesDel_addAF
Pathogenic
0.46
D
BayesDel_noAF
Pathogenic
0.42
CADD
Benign
22
DANN
Benign
0.80
DEOGEN2
Uncertain
0.69
D;D;.
Eigen
Uncertain
0.25
Eigen_PC
Benign
0.17
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Uncertain
0.93
.;D;D
M_CAP
Pathogenic
0.34
D
MetaRNN
Uncertain
0.71
D;D;D
MetaSVM
Pathogenic
0.83
D
MutationAssessor
Uncertain
2.6
M;M;.
PhyloP100
5.3
PrimateAI
Uncertain
0.75
T
PROVEAN
Benign
-0.31
N;N;N
REVEL
Pathogenic
0.70
Sift
Benign
0.10
T;T;T
Sift4G
Benign
0.36
T;T;.
Polyphen
0.95
P;P;.
Vest4
0.96
MutPred
0.62
Loss of stability (P = 0.2672);Loss of stability (P = 0.2672);.;
MVP
0.96
MPC
0.66
ClinPred
0.53
D
GERP RS
4.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.10
gMVP
0.96
Mutation Taster
=16/84
disease causing

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

Other links and lift over

dbSNP: rs1223603615; hg19: chr11-71152367; API