rs1555497657

Positions:

• chr16-2054377-C-G
• chr16-2054377-C-T

Variant summary

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

The NM_000548.5(TSC2):​c.418C>G​(p.Leu140Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. L140P) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 3.15

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.418C>G	p.Leu140Val	missense_variant	5/42	ENST00000219476.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC2	ENST00000219476.9	c.418C>G	p.Leu140Val	missense_variant	5/42	5	NM_000548.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:2

Uncertain significance, criteria provided, single submitter	curation	Sema4, Sema4	Dec 17, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Apr 19, 2022	The p.L140V variant (also known as c.418C>G), located in coding exon 4 of the TSC2 gene, results from a C to G substitution at nucleotide position 418. The leucine at codon 140 is replaced by valine, an amino acid with highly similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.30
BayesDel_addAF	Uncertain	0.16	D
BayesDel_noAF	Uncertain	-0.010
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.76	D;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Uncertain	0.27
Eigen_PC	Benign	0.19
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.91	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.26	D
MetaRNN	Uncertain	0.53	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.14	D
MutationAssessor	Uncertain	2.3	M;.;.;.;M;M;.;.;.;M;.;M;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.63	T
PROVEAN	Benign	-2.2	N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL	Uncertain	0.64
Sift	Benign	0.10	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G	Pathogenic	0.0	D;.;.;D;.;D;.;.;D;D;.;.;.;.;D
Polyphen		0.99	D;.;.;.;.;D;.;.;D;D;.;.;.;.;.
Vest4		0.77
MutPred		0.36		Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);.;Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);.;Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);Gain of ubiquitination at K144 (P = 0.0931);.;
MVP		0.82
ClinPred		0.93	D
GERP RS		3.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.18
gMVP		0.55

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: chr16-2104378;