chr7-129203569-C-T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 0P and 3B. BP4_ModerateBS1_Supporting

The NM_005631.5(SMO):​c.517C>T​(p.Arg173Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000667 in 1,601,930 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 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. R173H) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00070 ( 1 hom. )

Consequence

SMO
NM_005631.5 missense

Scores

8
11

Clinical Significance

Uncertain significance criteria provided, single submitter U:1O:1

Conservation

PhyloP100: 1.28

Publications

17 publications found
Variant links:
Genes affected
SMO (HGNC:11119): (smoothened, frizzled class receptor) The protein encoded by this gene is a G protein-coupled receptor that interacts with the patched protein, a receptor for hedgehog proteins. The encoded protein tranduces signals to other proteins after activation by a hedgehog protein/patched protein complex. [provided by RefSeq, Jul 2010]
SMO Gene-Disease associations (from GenCC):
  • Curry-Jones syndrome
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, G2P
  • congenital hypothalamic hamartoma syndrome
    Inheritance: AR Classification: STRONG, MODERATE Submitted by: G2P, Ambry Genetics, ClinGen
  • Hirschsprung disease
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • medulloblastoma
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -3 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.15216878).
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000335 (51/152328) while in subpopulation NFE AF = 0.000573 (39/68028). AF 95% confidence interval is 0.000431. There are 0 homozygotes in GnomAd4. There are 21 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SMONM_005631.5 linkc.517C>T p.Arg173Cys missense_variant Exon 2 of 12 ENST00000249373.8 NP_005622.1 Q99835
SMOXM_047420759.1 linkc.127C>T p.Arg43Cys missense_variant Exon 3 of 13 XP_047276715.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SMOENST00000249373.8 linkc.517C>T p.Arg173Cys missense_variant Exon 2 of 12 1 NM_005631.5 ENSP00000249373.3 Q99835
SMOENST00000655644.1 linkn.*381C>T non_coding_transcript_exon_variant Exon 3 of 12 ENSP00000499377.1 A0A590UJE7
SMOENST00000655644.1 linkn.*381C>T 3_prime_UTR_variant Exon 3 of 12 ENSP00000499377.1 A0A590UJE7

Frequencies

GnomAD3 genomes
AF:
0.000335
AC:
51
AN:
152210
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000145
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.000377
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000573
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000410
AC:
97
AN:
236830
AF XY:
0.000418
show subpopulations
Gnomad AFR exome
AF:
0.0000638
Gnomad AMR exome
AF:
0.0000292
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.000666
Gnomad NFE exome
AF:
0.000768
Gnomad OTH exome
AF:
0.000335
GnomAD4 exome
AF:
0.000702
AC:
1018
AN:
1449602
Hom.:
1
Cov.:
32
AF XY:
0.000678
AC XY:
489
AN XY:
721308
show subpopulations
African (AFR)
AF:
0.000149
AC:
5
AN:
33464
American (AMR)
AF:
0.0000224
AC:
1
AN:
44598
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26090
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39682
South Asian (SAS)
AF:
0.0000117
AC:
1
AN:
85738
European-Finnish (FIN)
AF:
0.000376
AC:
16
AN:
42508
Middle Eastern (MID)
AF:
0.000173
AC:
1
AN:
5764
European-Non Finnish (NFE)
AF:
0.000867
AC:
964
AN:
1111492
Other (OTH)
AF:
0.000498
AC:
30
AN:
60266
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
47
94
141
188
235
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
36
72
108
144
180
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000335
AC:
51
AN:
152328
Hom.:
0
Cov.:
32
AF XY:
0.000282
AC XY:
21
AN XY:
74484
show subpopulations
African (AFR)
AF:
0.000144
AC:
6
AN:
41578
American (AMR)
AF:
0.0000653
AC:
1
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.000377
AC:
4
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000573
AC:
39
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
Heterozygous variant carriers
0
3
6
9
12
15
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000699
Hom.:
0
Bravo
AF:
0.000355
TwinsUK
AF:
0.000809
AC:
3
ALSPAC
AF:
0.00208
AC:
8
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000581
AC:
5
ExAC
AF:
0.000362
AC:
44
EpiCase
AF:
0.000600
EpiControl
AF:
0.000773

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1Other:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Hamartoma of hypothalamus Uncertain:1
Jun 27, 2024
Clinical Genomics Laboratory, Washington University in St. Louis
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

A SMO c.517C>T (p.Arg173Cys) variant was identified at a heterozygous allelic fraction of 52%, a frequency which may be consistent with a germline variant. This variant has been reported in the literature in a patient with osteoarthritis (Styrkarsdottir U et al., PMID: 30374069) as well as during sequencing of a healthy, ancestrally diverse cohort (Bodian DL et al., PMID: 24728327) but to our knowledge, has not been reported in relation with an overgrowth disorder. It is observed on 1,069/1,601,930 alleles in the general population (gnomAD v.4.1.0), including one homozygote. Computational predictors suggest that the variant does not impact SMO function. Due to limited information, and based on ACMG/AMP guidelines for variant interpretation (Richards S et al., PMID: 25741868), the clinical significance of this variant is uncertain at this time. -

not specified Other:1
Sep 19, 2013
ITMI
Significance:not provided
Review Status:no classification provided
Collection Method:reference population

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.41
BayesDel_addAF
Benign
-0.34
T
BayesDel_noAF
Benign
-0.27
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.63
D
Eigen
Uncertain
0.29
Eigen_PC
Uncertain
0.31
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Benign
0.85
T
M_CAP
Benign
0.055
D
MetaRNN
Benign
0.15
T
MetaSVM
Benign
-0.37
T
MutationAssessor
Uncertain
2.8
M
PhyloP100
1.3
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-1.7
N
REVEL
Uncertain
0.32
Sift
Benign
0.18
T
Sift4G
Benign
0.17
T
Polyphen
0.91
P
Vest4
0.41
MVP
0.82
MPC
1.7
ClinPred
0.079
T
GERP RS
3.5
Varity_R
0.11
gMVP
0.59
Mutation Taster
=77/23
polymorphism

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: rs143083812; hg19: chr7-128843410; COSMIC: COSV50840329; COSMIC: COSV50840329; API