rs45517097

Positions:

• chr16-2053344-C-T

Variant summary

Our verdict is Benign. Variant got -17 ACMG points: 0P and 17B. BP4_Strong BP6_Very_Strong BP7 BS2

The NM_000548.5(TSC2):​c.228C>T​(p.His76=) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00203 in 1,580,544 control chromosomes in the GnomAD database, including 15 homozygotes. In-silico tool predicts a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0028 (6 hom., cov: 33)
  • Exomes 𝑓: 0.0019 (9 hom.)
• Consequence: TSC2 NM_000548.5 splice_region, synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:14 O:1
• Conservation: PhyloP100: -0.100

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]

ACMG classification

Verdict is Benign. Variant got -17 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.58).
• BP6: Variant 16-2053344-C-T is Benign according to our data. Variant chr16-2053344-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 49202.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr16-2053344-C-T is described in Lovd as [Benign]. Variant chr16-2053344-C-T is described in Lovd as [Likely_benign].
• BP7: Synonymous conserved (PhyloP=-0.1 with no splicing effect.
• BS2: High AC in GnomAd4 at 426 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TSC2	NM_000548.5	c.228C>T	p.His76=	splice_region_variant, synonymous_variant	4/42	ENST00000219476.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC2	ENST00000219476.9	c.228C>T	p.His76=	splice_region_variant, synonymous_variant	4/42	5	NM_000548.5

Frequencies

GnomAD3 genomes AF: 0.00281 AC: 427 AN: 152226 Hom.: 6 Cov.: 33

Gnomad AFR AF: 0.000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000196

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.0288

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00154

Gnomad OTH AF: 0.000478

GnomAD3 exomes AF: 0.00332 AC: 657 AN: 198132 Hom.: 4 AF XY: 0.00310 AC XY: 330 AN XY: 106394

Gnomad AFR exome AF: 0.000253

Gnomad AMR exome AF: 0.000206

Gnomad ASJ exome AF: 0.000222

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000398

Gnomad FIN exome AF: 0.0232

Gnomad NFE exome AF: 0.00272

Gnomad OTH exome AF: 0.00273

GnomAD4 exome AF: 0.00195 AC: 2778 AN: 1428200 Hom.: 9 Cov.: 31 AF XY: 0.00182 AC XY: 1287 AN XY: 707354

Gnomad4 AFR exome AF: 0.0000609

Gnomad4 AMR exome AF: 0.000226

Gnomad4 ASJ exome AF: 0.000118

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000615

Gnomad4 FIN exome AF: 0.0208

Gnomad4 NFE exome AF: 0.00147

Gnomad4 OTH exome AF: 0.00159

GnomAD4 genome AF: 0.00280 AC: 426 AN: 152344 Hom.: 6 Cov.: 33 AF XY: 0.00399 AC XY: 297 AN XY: 74502

Gnomad4 AFR AF: 0.000241

Gnomad4 AMR AF: 0.000196

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000414

Gnomad4 FIN AF: 0.0288

Gnomad4 NFE AF: 0.00153

Gnomad4 OTH AF: 0.000473

Alfa AF: 0.00147 Hom.: 0

Bravo AF: 0.000801

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:14 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:5

Benign, criteria provided, single submitter	clinical testing	GeneDx	Apr 17, 2012	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Feb 09, 2017	- -
Benign, no assertion criteria provided	clinical testing	Clinical Genetics, Academic Medical Center	-	- -
Benign, no assertion criteria provided	clinical testing	Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen	-	- -
Benign, criteria provided, single submitter	clinical testing	PreventionGenetics, part of Exact Sciences	-	- -

not provided Benign:4

Likely benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, Amsterdam University Medical Center	-	- -
Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Jun 17, 2021	- -
Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Dec 01, 2023	TSC2: BP4, BP7, BS1 -

Tuberous sclerosis 2 Benign:3

Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	May 30, 2017	- -
Benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -
Benign, criteria provided, single submitter	clinical testing	Invitae	Feb 01, 2024	- -

Tuberous sclerosis syndrome Benign:1 Other:1

not provided, no classification provided	curation	Tuberous sclerosis database (TSC2)	-	- -
Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 13, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Hereditary cancer-predisposing syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 07, 2014

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.58
CADD	Benign	6.3
DANN	Benign	0.69
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs45517097; hg19: chr16-2103345; COSMIC: COSV54776279; COSMIC: COSV54776279;