NM_000548.5:c.982G>A

Variant names:

• chr16-2060676-G-A
• NM_000548.5:c.982G>A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 4P and 2B. PM2 PM5 BP4_Moderate

The NM_000548.5(TSC2):​c.982G>A​(p.Ala328Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,712 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. 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. A328P) has been classified as Pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.81

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
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr16-2060676-G-C is described in Lovd as [Pathogenic].
• BP4: Computational evidence support a benign effect (MetaRNN=0.077910125).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC2	NM_000548.5	c.982G>A	p.Ala328Thr	missense_variant	Exon 11 of 42	ENST00000219476.9	NP_000539.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC2	ENST00000219476.9	c.982G>A	p.Ala328Thr	missense_variant	Exon 11 of 42	5	NM_000548.5	ENSP00000219476.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461712 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727156

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Tuberous sclerosis syndrome Uncertain:1

Jun 26, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces alanine with threonine at codon 328 of the TSC2 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with tuberous sclerosis complex in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.060
BayesDel_addAF	Benign	-0.0045	T
BayesDel_noAF	Benign	-0.24
CADD	Benign	9.1
DANN	Benign	0.44
DEOGEN2	Benign	0.32	T;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Benign	-0.86
Eigen_PC	Benign	-0.66
FATHMM_MKL	Benign	0.60	D
LIST_S2	Benign	0.72	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
M_CAP	Uncertain	0.093	D
MetaRNN	Benign	0.078	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.88	T
MutationAssessor	Benign	-1.9	N;.;.;.;N;N;.;.;.;N;.;N;.;.;.
PrimateAI	Benign	0.34	T
PROVEAN	Benign	0.56	N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL	Benign	0.28
Sift	Benign	1.0	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G	Benign	1.0	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen		0.0	B;.;.;.;B;B;.;.;B;B;.;.;.;.;.
Vest4		0.31
MutPred		0.39		Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);.;Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);.;Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);Gain of relative solvent accessibility (P = 0.0082);.;
MVP		0.55
ClinPred		0.070	T
GERP RS		3.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.029
gMVP		0.085

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: chr16-2110677;