7-124841164-T-G

Position:

• chr7-124841164-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_015450.3(POT1):​c.1178A>C​(p.His393Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar 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: 1.05

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 Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.1316782).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
POT1	NM_015450.3	c.1178A>C	p.His393Pro	missense_variant	14/19	ENST00000357628.8	NP_056265.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
POT1	ENST00000357628.8	c.1178A>C	p.His393Pro	missense_variant	14/19	2	NM_015450.3	ENSP00000350249	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

Tumor predisposition syndrome 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 25, 2021

This sequence change replaces histidine with proline at codon 393 of the POT1 protein (p.His393Pro). The histidine residue is weakly conserved and there is a moderate physicochemical difference between histidine and proline. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with POT1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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	0.091
BayesDel_addAF	Benign	-0.10	T
BayesDel_noAF	Benign	-0.38
CADD	Benign	19
DANN	Benign	0.80
DEOGEN2	Benign	0.20	T;T;T
Eigen	Benign	-0.62
Eigen_PC	Benign	-0.54
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Benign	0.73	T;T;.
M_CAP	Benign	0.016	T
MetaRNN	Benign	0.13	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Uncertain	2.4	M;.;.
MutationTaster	Benign	0.99	N;N
PrimateAI	Benign	0.22	T
PROVEAN	Benign	-1.8	N;N;.
REVEL	Benign	0.18
Sift	Benign	0.10	T;T;.
Sift4G	Benign	0.068	T;T;T
Polyphen		0.13	B;.;.
Vest4		0.36
MutPred		0.39		Gain of catalytic residue at P392 (P = 0.011);.;.;
MVP		0.53
MPC		0.18
ClinPred		0.29	T
GERP RS		1.9
Varity_R		0.62
gMVP		0.63

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs746416077; hg19: chr7-124481218;