chr7-124859006-A-G

Variant summary

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

The NM_015450.3(POT1):​c.653T>C​(p.Ile218Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000683 in 1,611,452 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 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. I218V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

POT1
NM_015450.3 missense

Scores

6
13

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 2.91

Publications

0 publications found
Variant links:
Genes affected
POT1 (HGNC:17284): (protection of telomeres 1) This gene is a member of the telombin family and encodes a nuclear protein involved in telomere maintenance. Specifically, this protein functions as a member of a multi-protein complex that binds to the TTAGGG repeats of telomeres, regulating telomere length and protecting chromosome ends from illegitimate recombination, catastrophic chromosome instability, and abnormal chromosome segregation. Increased transcriptional expression of this gene is associated with stomach carcinogenesis and its progression. Alternatively spliced transcript variants have been described. [provided by RefSeq, Jul 2008]
POT1 Gene-Disease associations (from GenCC):
  • pulmonary fibrosis and/or bone marrow failure syndrome, telomere-related, 8
    Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • tumor predisposition syndrome 3
    Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
  • glioma susceptibility 9
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • thyroid gland carcinoma
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
  • cerebroretinal microangiopathy with calcifications and cysts 3
    Inheritance: AR Classification: LIMITED Submitted by: G2P, 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=0.23570806).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
POT1NM_015450.3 linkc.653T>C p.Ile218Thr missense_variant Exon 9 of 19 ENST00000357628.8 NP_056265.2 Q9NUX5-1A0A024R739

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
POT1ENST00000357628.8 linkc.653T>C p.Ile218Thr missense_variant Exon 9 of 19 2 NM_015450.3 ENSP00000350249.3 Q9NUX5-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152160
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000120
AC:
3
AN:
250704
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.0000616
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:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000617
AC:
9
AN:
1459292
Hom.:
0
Cov.:
31
AF XY:
0.00000826
AC XY:
6
AN XY:
726024
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33422
American (AMR)
AF:
0.00
AC:
0
AN:
44652
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26088
East Asian (EAS)
AF:
0.0000253
AC:
1
AN:
39586
South Asian (SAS)
AF:
0.0000233
AC:
2
AN:
85984
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53348
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5756
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1110180
Other (OTH)
AF:
0.00
AC:
0
AN:
60276
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.497
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000131
AC:
2
AN:
152160
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74338
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41452
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68006
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.000108
Hom.:
0
Bravo
AF:
0.0000189
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:1
Dec 06, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); 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; This variant is associated with the following publications: (PMID: 28393830) -

Hereditary cancer-predisposing syndrome Uncertain:1
Apr 12, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.I218T variant (also known as c.653T>C), located in coding exon 5 of the POT1 gene, results from a T to C substitution at nucleotide position 653. The isoleucine at codon 218 is replaced by threonine, an amino acid with similar properties. This amino acid position is conserved. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Tumor predisposition syndrome 3 Uncertain:1
Sep 12, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 218 of the POT1 protein (p.Ile218Thr). This variant is present in population databases (rs376770473, gnomAD 0.007%). This variant has not been reported in the literature in individuals affected with POT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 541871). 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 POT1 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.19
BayesDel_addAF
Benign
-0.20
T
BayesDel_noAF
Benign
-0.34
CADD
Benign
22
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.65
D;D;D
Eigen
Benign
-0.13
Eigen_PC
Benign
-0.086
FATHMM_MKL
Uncertain
0.76
D
LIST_S2
Uncertain
0.91
D;D;.
M_CAP
Benign
0.017
T
MetaRNN
Benign
0.24
T;T;T
MetaSVM
Benign
-0.97
T
MutationAssessor
Uncertain
2.1
M;.;.
PhyloP100
2.9
PrimateAI
Benign
0.30
T
PROVEAN
Benign
-1.7
N;N;.
REVEL
Benign
0.10
Sift
Uncertain
0.020
D;D;.
Sift4G
Benign
0.16
T;T;D
Polyphen
0.40
B;.;.
Vest4
0.52
MVP
0.46
MPC
1.3
ClinPred
0.12
T
GERP RS
2.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.21
gMVP
0.80
Mutation Taster
=78/22
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs376770473; hg19: chr7-124499060; API