rs768012192

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_024577.4(SH3TC2):​c.1318C>T​(p.Arg440Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000366 in 1,613,834 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict 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. R440H) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000036 ( 0 hom. )

Consequence

SH3TC2
NM_024577.4 missense

Scores

1
18

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 4.84

Publications

0 publications found
Variant links:
Genes affected
SH3TC2 (HGNC:29427): (SH3 domain and tetratricopeptide repeats 2) This gene encodes a protein with two N-terminal Src homology 3 (SH3) domains and 10 tetratricopeptide repeat (TPR) motifs, and is a member of a small gene family. The gene product has been proposed to be an adapter or docking molecule. Mutations in this gene result in autosomal recessive Charcot-Marie-Tooth disease type 4C, a childhood-onset neurodegenerative disease characterized by demyelination of motor and sensory neurons. [provided by RefSeq, Jul 2008]
SH3TC2 Gene-Disease associations (from GenCC):
  • autosomal recessive hereditary demyelinating motor and sensory neuropathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • Charcot-Marie-Tooth disease type 4C
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Ambry Genetics
  • susceptibility to mononeuropathy of the median nerve, mild
    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 -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.14102572).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SH3TC2NM_024577.4 linkc.1318C>T p.Arg440Cys missense_variant Exon 11 of 17 ENST00000515425.6 NP_078853.2 Q8TF17-1A0A514TP98

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SH3TC2ENST00000515425.6 linkc.1318C>T p.Arg440Cys missense_variant Exon 11 of 17 1 NM_024577.4 ENSP00000423660.1 Q8TF17-1

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152164
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000724
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000279
AC:
7
AN:
250612
AF XY:
0.0000442
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:
0.0000619
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000363
AC:
53
AN:
1461670
Hom.:
0
Cov.:
77
AF XY:
0.0000344
AC XY:
25
AN XY:
727142
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44702
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.0000188
AC:
1
AN:
53302
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000468
AC:
52
AN:
1111952
Other (OTH)
AF:
0.00
AC:
0
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
4
8
13
17
21
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152164
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74344
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41434
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.542
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000773
Hom.:
0
Bravo
AF:
0.0000340
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ExAC
AF:
0.0000330
AC:
4
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Charcot-Marie-Tooth disease Uncertain:1
-
Molecular Genetics Laboratory, London Health Sciences Centre
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Tip-toe gait Uncertain:1
Nov 27, 2020
Practice for Gait Abnormalities, David Pomarino, Competency Network Toe Walking c/o Practice Pomarino
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Hereditary motor sensory neuropathy (HMSN), also known as Charcot-Marie-Tooth Disease (CMT), is the most commonly inherited peripheral polyneuropathy. It constitutes a group of inherited, progressive, motor and sensory peripheral nerve disorders with properties of demyelination, axonal degeneration, or both. It is classified by clinical characteristics, modes of inheritance, electrophysiologic features, metabolic defects, and specific gene markers. Our patients all walk on tiptoe, so they show similar symptoms. When we genetically test them with our toe walking panel, we find that around 90 per cent of them have a genetic variant that explains their toe walking. These can be assigned, for example, to the area of myopathies (such as variants of the COL6A3 gene), the area of hereditary neuropathies (such as variants of the KMT2C gene) or the area of metabolic diseases (such as variants of the PYGM gene). In a smaller group of patients with almost identical symptoms, no abnormality is found in the genes of our panel, but spastic paraplegia can be detected. In another small group of our toe walkers, no abnormalities can be detected in the genes analysed in our toe walking panel, nor do they suffer from spastic paraplegia, as is also the case with healthy children. In contrast to these, however, they show a tiptoe gait. These patients suffer from infantile cerebral palsy, in which toe walking can also be observed. -

not provided Uncertain:1
Feb 22, 2018
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Charcot-Marie-Tooth disease type 4 Uncertain:1
Jan 11, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 440 of the SH3TC2 protein (p.Arg440Cys). This variant is present in population databases (rs768012192, gnomAD 0.007%). This missense change has been observed in individual(s) with clinical features of Charcot-Marie-Tooth disease (PMID: 32376792). ClinVar contains an entry for this variant (Variation ID: 583032). 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 not expected to disrupt SH3TC2 protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.073
BayesDel_addAF
Benign
-0.19
T
BayesDel_noAF
Benign
-0.33
CADD
Benign
20
DANN
Benign
0.93
DEOGEN2
Benign
0.071
T;.
Eigen
Benign
-0.22
Eigen_PC
Benign
-0.095
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Benign
0.67
T;T
M_CAP
Benign
0.041
D
MetaRNN
Benign
0.14
T;T
MetaSVM
Benign
-0.53
T
MutationAssessor
Benign
0.0
N;.
PhyloP100
4.8
PrimateAI
Benign
0.25
T
PROVEAN
Benign
0.44
N;N
REVEL
Benign
0.20
Sift
Benign
0.20
T;T
Sift4G
Benign
0.090
T;T
Polyphen
0.28
B;.
Vest4
0.17
MVP
0.81
MPC
0.050
ClinPred
0.18
T
GERP RS
4.6
Varity_R
0.090
gMVP
0.28
Mutation Taster
=71/29
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: rs768012192; hg19: chr5-148407977; COSMIC: COSV60468239; COSMIC: COSV60468239; API