dbSNP rs1555514052: TSC2:p.Pro1389_Glu1390insProLeuSerLysSerSerSerSerPro (chr16-2084361-A-AGCCCCTGAGCAAGTCCAGCTCCTCTCC) – ACMG Classification: Uncertain_significance (4 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2PM4

The NM_000548.5(TSC2):c.4140_4166dupGCCCCTGAGCAAGTCCAGCTCCTCTCC(p.Pro1389_Glu1390insProLeuSerLysSerSerSerSerPro) variant causes a disruptive inframe insertion change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. P1389P) has been classified as Benign.

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Failed GnomAD Quality Control

Consequence

TSC2
NM_000548.5 disruptive_inframe_insertion

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 2.82

Variant links:

Genes affected

TSC2 (HGNC:12363): (TSC complex subunit 2) This gene is a tumor suppressor gene that encodes the growth inhibitory protein tuberin. Tuberin interacts with hamartin to form the TSC protein complex which functions in the control of cell growth. This TSC protein complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]

TSC2 links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PM4

Nonframeshift variant in NON repetitive region in NM_000548.5.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5 link	c.4140_4166dupGCCCCTGAGCAAGTCCAGCTCCTCTCC	p.Pro1389_Glu1390insProLeuSerLysSerSerSerSerPro	disruptive_inframe_insertion	Exon 34 of 42	ENST00000219476.9	NP_000539.2	P49815-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9 link	c.4140_4166dupGCCCCTGAGCAAGTCCAGCTCCTCTCC	p.Pro1389_Glu1390insProLeuSerLysSerSerSerSerPro	disruptive_inframe_insertion	Exon 34 of 42	5	NM_000548.5	ENSP00000219476.3		P49815-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

Data not reliable, filtered out with message: AS_VQSR

AF:

0.00000137

AC:

AN:

1460316

Hom.:

Cov.:

AF XY:

0.00000275

AC XY:

AN XY:

726468

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000180

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Tuberous sclerosis 2

Uncertain:1

Oct 11, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant, c.4140_4166dup, results in the insertion of 9 amino acid(s) of the TSC2 protein (p.Pro1381_Pro1389dup), but otherwise preserves the integrity of the reading frame. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TSC2-related conditions. ClinVar contains an entry for this variant (Variation ID: 535853). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -

Hereditary cancer-predisposing syndrome

Uncertain:1

Nov 16, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.4140_4166dup27 variant (also known as p.P1381_P1389dup), located in coding exon 33 of the TSC2 gene, results from an in-frame duplication of 27 nucleotides at nucleotide positions 4140 to 4166. This results in the duplication of 9 extra residues (PLSKSSSSP) between codons 1381 and 1389. This amino acid region is well conserved in available vertebrate species. In addition, this alteration is predicted to be neutral by in silico analysis (Choi Y et al. PLoS ONE. 2012; 7(10):e46688). 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

Splicing

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

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