chr16-2071820-C-A

Variant names:

• chr16-2071820-C-A
• rs1270679683
• NM_000548.5:c.1983C>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_000548.5(TSC2):​c.1983C>A​(p.Gly661Gly) 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. G661G) 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: Not reported in ClinVar
• Conservation: PhyloP100: -1.56
• 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 -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.75).
• BP7: Synonymous conserved (PhyloP=-1.56 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.1983C>A	p.Gly661Gly	synonymous	Exon 19 of 42	NP_000539.2
	TSC2	NM_001406663.1		c.1983C>A	p.Gly661Gly	synonymous	Exon 19 of 42	NP_001393592.1
	TSC2	NM_001114382.3		c.1983C>A	p.Gly661Gly	synonymous	Exon 19 of 41	NP_001107854.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC2	ENST00000219476.9	TSL:5 MANE Select	c.1983C>A	p.Gly661Gly	synonymous	Exon 19 of 42	ENSP00000219476.3
	TSC2	ENST00000350773.9	TSL:1	c.1983C>A	p.Gly661Gly	synonymous	Exon 19 of 41	ENSP00000344383.4
	TSC2	ENST00000401874.7	TSL:1	c.1983C>A	p.Gly661Gly	synonymous	Exon 19 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: 1448188 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 719190

African (AFR) AF: 0.00 AC: 0 AN: 33166

American (AMR) AF: 0.00 AC: 0 AN: 43490

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25762

East Asian (EAS) AF: 0.00 AC: 0 AN: 39074

South Asian (SAS) AF: 0.00 AC: 0 AN: 83954

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51020

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5748

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1106178

Other (OTH) AF: 0.00 AC: 0 AN: 59796

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.75
CADD	Benign	0.70
DANN	Benign	0.41
PhyloP100		-1.6

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: rs1270679683; hg19: chr16-2121821;