rs45517249

Positions:

• chr16-2075838-C-G
• chr16-2075838-C-T

Variant summary

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

The NM_000548.5(TSC2):​c.2585C>G​(p.Ala862Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,460,732 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A862T) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.94

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.2585C>G	p.Ala862Gly	missense_variant	23/42	ENST00000219476.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC2	ENST00000219476.9	c.2585C>G	p.Ala862Gly	missense_variant	23/42	5	NM_000548.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460732 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 726700

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: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

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

Invitae

Jan 29, 2021

This variant is not present in population databases (ExAC no frequency). This sequence change replaces alanine with glycine at codon 862 of the TSC2 protein (p.Ala862Gly). The alanine residue is highly conserved and there is a small physicochemical difference between alanine and glycine. This variant has not been reported in the literature in individuals with TSC2-related conditions. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt TSC2 protein function. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.34
BayesDel_addAF	Pathogenic	0.28	D
BayesDel_noAF	Pathogenic	0.16
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.60	D;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Benign	0.062
Eigen_PC	Benign	0.14
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.89	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.14	D
MetaRNN	Uncertain	0.61	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	-0.00030	T
MutationAssessor	Benign	0.90	L;.;.;.;L;L;.;.;.;L;.;L;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.73	T
PROVEAN	Benign	-1.7	N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL	Uncertain	0.62
Sift	Benign	0.53	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G	Benign	0.43	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen		0.52	P;.;.;.;P;B;.;.;P;P;.;.;.;.;.
Vest4		0.70
MutPred		0.40		Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);.;Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);.;Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);Loss of stability (P = 0.0419);.;
MVP		0.83
ClinPred		0.78	D
GERP RS		5.0
Varity_R		0.25
gMVP		0.32

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr16-2125839;