16-2072271-C-T

Position:

• chr16-2072271-C-T

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_Moderate BP6 BS2

The NM_000548.5(TSC2):​c.2128C>T​(p.Leu710Leu) variant causes a synonymous change. The variant allele was found at a frequency of 0.00000616 in 1,461,762 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. LG710L?) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: TSC2 NM_000548.5 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:6
• Conservation: PhyloP100: 6.12

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 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -7 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.31).
• BP6: Variant 16-2072271-C-T is Benign according to our data. Variant chr16-2072271-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 467926.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=4, Uncertain_significance=1, Benign=1}.
• BS2: High AC in GnomAdExome4 at 9 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TSC2	NM_000548.5	c.2128C>T	p.Leu710Leu	synonymous_variant	20/42	ENST00000219476.9	NP_000539.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9	c.2128C>T	p.Leu710Leu	synonymous_variant	20/42	5	NM_000548.5	ENSP00000219476.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251182 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135880

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000653

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461762 Hom.: 0 Cov.: 32 AF XY: 0.00000688 AC XY: 5 AN XY: 727158

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: 0.000104

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:6

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Tuberous sclerosis 2 Benign:3

Likely benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 10, 2024	- -
Benign, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Nov 07, 2021	- -
Likely benign, criteria provided, single submitter	clinical testing	KCCC/NGS Laboratory, Kuwait Cancer Control Center	Jul 07, 2023	- -

not provided Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Aug 25, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	May 29, 2024	- -

Hereditary cancer-predisposing syndrome Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	Feb 18, 2020	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. -
Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Mar 15, 2022	- -

TSC2-related disorder Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

May 23, 2019

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.31
CADD	Benign	8.3
DANN	Benign	0.59

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.090		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: rs1225700612; hg19: chr16-2122272;