16-2053374-G-T

Variant names:

• chr16-2053374-G-T
• rs397514912
• NM_000548.5:c.258G>T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_000548.5(TSC2):​c.258G>T​(p.Ala86Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. A86A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TSC2 NM_000548.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -1.86
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• tuberous sclerosis

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• tuberous sclerosis 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, Ambry Genetics
• lymphangioleiomyomatosis

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• tuberous sclerosis complex

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BP6: Variant 16-2053374-G-T is Benign according to our data. Variant chr16-2053374-G-T is described in ClinVar as Likely_benign. ClinVar VariationId is 1793505.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-1.86 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000548.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC2	NM_000548.5	MANE Select	c.258G>T	p.Ala86Ala	synonymous	Exon 4 of 42	NP_000539.2
	TSC2	NM_001406680.1		c.-559G>T		5_prime_UTR_premature_start_codon_gain	Exon 4 of 42	NP_001393609.1
	TSC2	NM_001406681.1		c.-188G>T		5_prime_UTR_premature_start_codon_gain	Exon 4 of 40	NP_001393610.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC2	ENST00000219476.9	TSL:5 MANE Select	c.258G>T	p.Ala86Ala	synonymous	Exon 4 of 42	ENSP00000219476.3
	TSC2	ENST00000350773.9	TSL:1	c.258G>T	p.Ala86Ala	synonymous	Exon 4 of 41	ENSP00000344383.4
	TSC2	ENST00000401874.7	TSL:1	c.258G>T	p.Ala86Ala	synonymous	Exon 4 of 40	ENSP00000384468.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1439108 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 713726

African (AFR) AF: 0.00 AC: 0 AN: 33090

American (AMR) AF: 0.00 AC: 0 AN: 41696

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25648

East Asian (EAS) AF: 0.00 AC: 0 AN: 38612

South Asian (SAS) AF: 0.00 AC: 0 AN: 82412

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50938

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5250

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1101990

Other (OTH) AF: 0.00 AC: 0 AN: 59472

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary cancer-predisposing syndrome Benign:1

Jun 21, 2022

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	0.21
DANN	Benign	0.61
PhyloP100		-1.9
PromoterAI		0.021	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.070		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs397514912; hg19: chr16-2103375;