chr16-2053443-G-T

Variant names:

• chr16-2053443-G-T
• rs754348511
• NM_000548.5:c.327G>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.327G>T​(p.Val109Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000704 in 1,421,184 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 Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. V109V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: TSC2 NM_000548.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 0.368
• 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=-0.63).
• BP6: Variant 16-2053443-G-T is Benign according to our data. Variant chr16-2053443-G-T is described in ClinVar as [Likely_benign]. Clinvar id is 1919165.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=0.368 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5	c.327G>T	p.Val109Val	synonymous_variant	Exon 4 of 42	ENST00000219476.9	NP_000539.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9	c.327G>T	p.Val109Val	synonymous_variant	Exon 4 of 42	5	NM_000548.5	ENSP00000219476.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 7.04e-7 AC: 1 AN: 1421184 Hom.: 0 Cov.: 31 AF XY: 0.00000142 AC XY: 1 AN XY: 703144

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000307 AC: 1 AN: 32586

American (AMR) AF: 0.00 AC: 0 AN: 38712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25366

East Asian (EAS) AF: 0.00 AC: 0 AN: 37450

South Asian (SAS) AF: 0.00 AC: 0 AN: 80858

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 49716

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5596

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1092082

Other (OTH) AF: 0.00 AC: 0 AN: 58818

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Tuberous sclerosis 2 Benign:1

Apr 06, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.63
CADD	Benign	4.6
DANN	Benign	0.63
PhyloP100		0.37
PromoterAI		0.015	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs754348511; hg19: chr16-2103444;