16-2048066-G-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_ModeratePM2PP3_Strong

The NM_000548.5(TSC2):c.-30+1G>T variant causes a splice donor change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000035 in 1,427,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 7.8e-7 ( 0 hom. )

Consequence

TSC2
NM_000548.5 splice_donor

Scores

Splicing: ADA: 1.000

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4O:1

Conservation

PhyloP100: 1.62

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:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

PVS1

Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.0147492625 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.

PM2

Very rare variant in population databases, with high coverage;

PP3

Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TSC2	NM_000548.5 linkuse as main transcript	c.-30+1G>T		splice_donor_variant		ENST00000219476.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC2	ENST00000219476.9 linkuse as main transcript	c.-30+1G>T		splice_donor_variant		5	NM_000548.5		P49815-1

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152184

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000724

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

7.84e-7

AC:

AN:

1275592

Hom.:

Cov.:

AF XY:

0.00000161

AC XY:

AN XY:

620434

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:

9.71e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152296

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74466

show subpopulations

Gnomad4 AFR

AF:

0.0000722

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Tuberous sclerosis syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Dec 18, 2023

This variant causes a G to T nucleotide substitution at the +1 position of noncoding intron 1 of the TSC2 gene. Splice site prediction tools suggest that this variant may have a significant impact on RNA splicing, although this prediction has not been confirmed in published RNA studies. This variant has not been reported in individuals affected with TSC2-related disorders in the literature. This variant has been identified in 2/31366 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Tuberous sclerosis 2

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 22, 2023

This variant occurs in a non-coding region of the TSC2 gene. It does not change the encoded amino acid sequence of the TSC2 protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs587778004, gnomAD 0.02%). 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: 133423). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jun 16, 2023

In silico analysis supports a deleterious effect on splicing; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 24728327) -

Isolated focal cortical dysplasia type II

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Sep 02, 2022

- -

not specified

Other:1

not provided, no classification provided

reference population

ITMI

Sep 19, 2013

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.66

Cadd

Pathogenic

Dann

Benign

0.64

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.80

SpliceAI score (max)

0.96

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.96

Position offset: -1

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

Other links and lift over