NM_025099.6:c.2260C>G

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_025099.6(CTC1):​c.2260C>G​(p.Pro754Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000882 in 1,587,338 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000049 ( 0 hom. )

Consequence

CTC1
NM_025099.6 missense

Scores

19

Clinical Significance

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

Conservation

PhyloP100: -0.543

Publications

0 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 -4 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.044857085).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CTC1NM_025099.6 linkc.2260C>G p.Pro754Ala missense_variant Exon 13 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.2260C>G p.Pro754Ala missense_variant Exon 13 of 23 NM_025099.6 ENSP00000498499.1 Q2NKJ3-1

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152166
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000169
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000488
AC:
7
AN:
1435056
Hom.:
0
Cov.:
33
AF XY:
0.00000420
AC XY:
3
AN XY:
713468
show subpopulations
African (AFR)
AF:
0.000188
AC:
6
AN:
31938
American (AMR)
AF:
0.00
AC:
0
AN:
38056
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
23870
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39642
South Asian (SAS)
AF:
0.00
AC:
0
AN:
82110
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52476
Middle Eastern (MID)
AF:
0.000179
AC:
1
AN:
5590
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1102286
Other (OTH)
AF:
0.00
AC:
0
AN:
59088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.482
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

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:
0.0000460
AC:
7
AN:
152282
Hom.:
0
Cov.:
32
AF XY:
0.0000806
AC XY:
6
AN XY:
74466
show subpopulations
African (AFR)
AF:
0.000168
AC:
7
AN:
41548
American (AMR)
AF:
0.00
AC:
0
AN:
15298
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.432
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.0000712
Hom.:
0
Bravo
AF:
0.0000227

ClinVar

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

Submissions by phenotype

Dyskeratosis congenita Uncertain:2
Sep 16, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 754 of the CTC1 protein (p.Pro754Ala). This variant is present in population databases (rs370354906, gnomAD 0.03%). 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: 568849). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt CTC1 protein function with a negative predictive value of 80%. 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. -

Oct 13, 2021
Sema4, Sema4
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:curation

- -

Cerebroretinal microangiopathy with calcifications and cysts 1 Uncertain:1
Mar 07, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Sep 10, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.2260C>G (p.P754A) alteration is located in exon 13 (coding exon 13) of the CTC1 gene. This alteration results from a C to G substitution at nucleotide position 2260, causing the proline (P) at amino acid position 754 to be replaced by an alanine (A). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.062
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.42
CADD
Benign
3.2
DANN
Benign
0.30
DEOGEN2
Benign
0.33
T
Eigen
Benign
-1.6
Eigen_PC
Benign
-1.7
FATHMM_MKL
Benign
0.037
N
LIST_S2
Benign
0.59
T
M_CAP
Benign
0.027
D
MetaRNN
Benign
0.045
T
MetaSVM
Benign
-0.81
T
MutationAssessor
Benign
1.4
L
PhyloP100
-0.54
PrimateAI
Benign
0.23
T
PROVEAN
Benign
-1.1
N
REVEL
Benign
0.19
Sift
Benign
0.84
T
Sift4G
Benign
0.56
T
Polyphen
0.058
B
Vest4
0.10
MutPred
0.12
Loss of disorder (P = 0.0807);
MVP
0.17
MPC
0.12
ClinPred
0.053
T
GERP RS
-6.9
RBP_binding_hub_radar
0.97
RBP_regulation_power_radar
2.1
Varity_R
0.11
gMVP
0.099
Mutation Taster
=98/2
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs370354906; hg19: chr17-8135346; API