rs202187871

Positions:

• chr7-124858989-C-G
• chr7-124858989-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_015450.3(POT1):​c.670G>C​(p.Asp224His) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic 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. D224N) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: POT1 NM_015450.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.12

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.977

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
POT1	NM_015450.3	c.670G>C	p.Asp224His	missense_variant	9/19	ENST00000357628.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
POT1	ENST00000357628.8	c.670G>C	p.Asp224His	missense_variant	9/19	2	NM_015450.3	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 22, 2023

The p.D224H variant (also known as c.670G>C), located in coding exon 5 of the POT1 gene, results from a G to C substitution at nucleotide position 670. The aspartic acid at codon 224 is replaced by histidine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.39	D
BayesDel_noAF	Pathogenic	0.33
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.93	D;D;D
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.95	D;D;.
M_CAP	Uncertain	0.29	D
MetaRNN	Pathogenic	0.98	D;D;D
MetaSVM	Uncertain	0.35	D
MutationAssessor	Uncertain	2.7	M;.;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.56	T
PROVEAN	Uncertain	-4.4	D;D;.
REVEL	Pathogenic	0.71
Sift	Pathogenic	0.0	D;D;.
Sift4G	Pathogenic	0.0	D;D;D
Polyphen		1.0	D;.;.
Vest4		0.94
MutPred		0.89		Loss of catalytic residue at D224 (P = 0.0171);.;.;
MVP		0.92
MPC		2.2
ClinPred		1.0	D
GERP RS		6.0
Varity_R		0.87
gMVP		0.95

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.24		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.24		Position offset: -32

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chr7-124499043; COSMIC: COSV62928673;