chr7-128957272-TG-T

Position:

• chr7-128957272-TG-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_012470.4(TNPO3):​c.2754del​(p.Phe918LeufsTer22) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: TNPO3 NM_012470.4 frameshift
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.40

Genes affected

TNPO3 (HGNC:17103): (transportin 3) The protein encoded by this gene is a nuclear import receptor for serine/arginine-rich (SR) proteins such as the splicing factors SFRS1 and SFRS2. The encoded protein has also been shown to be involved in HIV-1 infection, apparently through interaction with the HIV-1 capsid protein. Several protein-coding and non-coding transcript variants have been found for this gene. [provided by RefSeq, Apr 2020]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most 50 bp of the penultimate exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.00649 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TNPO3	NM_012470.4	c.2754del	p.Phe918LeufsTer22	frameshift_variant	22/23	ENST00000265388.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TNPO3	ENST00000265388.10	c.2754del	p.Phe918LeufsTer22	frameshift_variant	22/23	1	NM_012470.4	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

Autosomal dominant limb-girdle muscular dystrophy type 1F Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 12, 2022

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. This variant results in an extension of the TNPO3 protein. Other variant(s) that result in a similarly extended protein product (p.*924Cysext*15) have been determined to be pathogenic (PMID: 23543484, 23667635). This suggests that these extensions are likely to be disease-causing. This variant has not been reported in the literature in individuals affected with TNPO3-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change results in a frameshift in the TNPO3 gene (p.Phe918Leufs*22). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 6 amino acid(s) of the TNPO3 protein and extend the protein by 15 additional amino acid residues. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		Details are displayed if max score is > 0.2

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: chr7-128597326;