rs1064793797

Positions:

• chr16-2083763-G-A
• chr16-2083763-G-C
• chr16-2083763-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000548.5(TSC2):​c.3952G>A​(p.Glu1318Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000000686 in 1,458,286 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. E1318E) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.89

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 Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TSC2	NM_000548.5	c.3952G>A	p.Glu1318Lys	missense_variant	33/42	ENST00000219476.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC2	ENST00000219476.9	c.3952G>A	p.Glu1318Lys	missense_variant	33/42	5	NM_000548.5

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1458286 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 725156

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Tuberous sclerosis 2 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 13, 2019

Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a TSC2-related disease. This sequence change replaces glutamic acid with lysine at codon 1318 of the TSC2 protein (p.Glu1318Lys). The glutamic acid residue is highly conserved and there is a small physicochemical difference between glutamic acid and lysine. In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.18
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.51	D;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Benign	0.082
Eigen_PC	Benign	0.093
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.96	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.28	D
MetaRNN	Uncertain	0.49	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Uncertain	0.35	D
MutationAssessor	Benign	1.8	L;.;.;.;.;.;.;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.59	T
PROVEAN	Benign	-1.8	N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL	Uncertain	0.56
Sift	Benign	0.071	T;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Sift4G	Benign	0.32	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen		0.98	D;.;.;.;P;P;.;.;P;P;.;.;.;.;.
Vest4		0.55
MutPred		0.33		Gain of ubiquitination at E1318 (P = 0.0016);.;.;.;.;.;.;Gain of ubiquitination at E1318 (P = 0.0016);.;.;.;.;.;.;.;
MVP		0.94
ClinPred		0.67	D
GERP RS		4.1
Varity_R		0.15
gMVP		0.47

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

Publications

LitVar

Other links and lift over

dbSNP: rs1064793797; hg19: chr16-2133764;