rs185346402

Variant summary

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

The NM_025099.6(CTC1):​c.556G>C​(p.Val186Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000567 in 1,614,150 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. V186M) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00032 ( 0 hom., cov: 31)
Exomes 𝑓: 0.00059 ( 0 hom. )

Consequence

CTC1
NM_025099.6 missense

Scores

1
8
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:9

Conservation

PhyloP100: 1.56

Publications

3 publications found
Variant links:
Genes affected
CTC1 (HGNC:26169): (CST telomere replication complex component 1) This gene encodes a component of the CST complex. This complex plays an essential role in protecting telomeres from degradation. This protein also forms a heterodimer with the CST complex subunit STN1 to form the enzyme alpha accessory factor. This enzyme regulates DNA replication. Mutations in this gene are the cause of cerebroretinal microangiopathy with calcifications and cysts. Alternate splicing results in both coding and non-coding variants. [provided by RefSeq, Mar 2012]
CTC1 Gene-Disease associations (from GenCC):
  • cerebroretinal microangiopathy with calcifications and cysts 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Ambry Genetics, G2P
  • dyskeratosis congenita
    Inheritance: AR, AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, Orphanet
  • Coats plus syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

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=0.11000073).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CTC1NM_025099.6 linkc.556G>C p.Val186Leu missense_variant Exon 4 of 23 ENST00000651323.1 NP_079375.3 Q2NKJ3-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CTC1ENST00000651323.1 linkc.556G>C p.Val186Leu missense_variant Exon 4 of 23 NM_025099.6 ENSP00000498499.1 Q2NKJ3-1

Frequencies

GnomAD3 genomes
AF:
0.000322
AC:
49
AN:
152158
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.000145
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000458
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000942
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000485
Gnomad OTH
AF:
0.000958
GnomAD2 exomes
AF:
0.000353
AC:
88
AN:
249400
AF XY:
0.000325
show subpopulations
Gnomad AFR exome
AF:
0.000194
Gnomad AMR exome
AF:
0.000724
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000464
Gnomad NFE exome
AF:
0.000495
Gnomad OTH exome
AF:
0.000495
GnomAD4 exome
AF:
0.000593
AC:
867
AN:
1461874
Hom.:
0
Cov.:
31
AF XY:
0.000576
AC XY:
419
AN XY:
727232
show subpopulations
African (AFR)
AF:
0.000119
AC:
4
AN:
33480
American (AMR)
AF:
0.000760
AC:
34
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:
0.000112
AC:
6
AN:
53418
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000728
AC:
809
AN:
1111996
Other (OTH)
AF:
0.000232
AC:
14
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.452
Heterozygous variant carriers
0
45
90
135
180
225
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:
0.000322
AC:
49
AN:
152276
Hom.:
0
Cov.:
31
AF XY:
0.000336
AC XY:
25
AN XY:
74466
show subpopulations
African (AFR)
AF:
0.000144
AC:
6
AN:
41556
American (AMR)
AF:
0.000458
AC:
7
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5184
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4822
European-Finnish (FIN)
AF:
0.0000942
AC:
1
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000485
AC:
33
AN:
68020
Other (OTH)
AF:
0.000948
AC:
2
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.505
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:
0.000445
Hom.:
0
Bravo
AF:
0.000404
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00182
AC:
7
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000479
AC:
4
ExAC
AF:
0.000331
AC:
40
EpiCase
AF:
0.000273
EpiControl
AF:
0.000356

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cerebroretinal microangiopathy with calcifications and cysts 1 Uncertain:3
Jul 15, 2021
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

May 26, 2020
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on the classification scheme VCGS_Germline_v1.1.1, this variant is classified as 3B-VUS. Following criteria are met: 0102 - Loss-of-function is a known mechanism of disease for this gene. (N) 0107 - This gene is known to be associated with autosomal dominant disease. (N) 0200 - Variant is predicted to result in a missense amino acid change from valine to leucine (exon 4). (N) 0251 - Variant is heterozygous. (N) 0304 - Variant is present in gnomAD <0.01 for a recessive condition (101 heterozygotes, 0 homozygotes). (P) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (18 heterozygotes, 0 homozygotes). (N) 0502 - Missense variant with conflicting in silico predictions and/or uninformative conservation. (N) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (N) 0705 - No comparable variants have previous evidence for pathogenicity. (N) 0807 - Variant has not previously been reported in a clinical context. (N) 0905 - No segregation evidence has been identified for this variant. (N) 1007 - No published functional evidence has been identified for this variant. (N) 1208 - Inheritance information for this variant is not currently available. (N) Legend: (P) - Pathogenic, (N) - Neutral, (B) - Benign -

Mar 19, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dyskeratosis congenita Uncertain:3
Nov 02, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 186 of the CTC1 protein (p.Val186Leu). This variant is present in population databases (rs185346402, gnomAD 0.08%). This variant has not been reported in the literature in individuals affected with CTC1-related conditions. ClinVar contains an entry for this variant (Variation ID: 459604). 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 CTC1 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. -

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

May 24, 2021
Sema4, Sema4
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:curation

- -

not specified Uncertain:1
Mar 27, 2019
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Aug 26, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.556G>C (p.V186L) alteration is located in exon 4 (coding exon 4) of the CTC1 gene. This alteration results from a G to C substitution at nucleotide position 556, causing the valine (V) at amino acid position 186 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1
Mar 28, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.21
BayesDel_addAF
Benign
-0.14
T
BayesDel_noAF
Uncertain
0.010
CADD
Benign
21
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.48
T
Eigen
Benign
0.048
Eigen_PC
Benign
0.099
FATHMM_MKL
Uncertain
0.78
D
LIST_S2
Benign
0.81
T
M_CAP
Benign
0.048
D
MetaRNN
Benign
0.11
T
MetaSVM
Uncertain
0.11
D
MutationAssessor
Uncertain
2.6
M
PhyloP100
1.6
PrimateAI
Uncertain
0.51
T
PROVEAN
Benign
-1.7
N
REVEL
Uncertain
0.56
Sift
Benign
0.090
T
Sift4G
Pathogenic
0.0
D
Polyphen
0.48
P
Vest4
0.59
MutPred
0.52
Gain of sheet (P = 0.0827);
MVP
0.74
MPC
0.24
ClinPred
0.036
T
GERP RS
4.5
Varity_R
0.19
gMVP
0.46
Mutation Taster
=95/5
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: rs185346402; hg19: chr17-8141440; COSMIC: COSV106102260; COSMIC: COSV106102260; API