NM_000368.5:c.149T>C

Variant names:

• chr9-132927262-A-G
• rs118203341
• NM_000368.5:c.149T>C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_000368.5(TSC1):​c.149T>C​(p.Leu50Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: TSC1 NM_000368.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1 O:1
• Conservation: PhyloP100: 9.02

Genes affected

TSC1 (HGNC:12362): (TSC complex subunit 1) This gene is a tumor suppressor gene that encodes the growth inhibitory protein hamartin. The encoded protein interacts with and stabilizes the GTPase activating protein tuberin. This hamartin-tuberin complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. This protein also functions as a co-chaperone for Hsp90 that inhibits its ATPase activity. This protein functions as a facilitator of Hsp90-mediated folding of kinase and non-kinase clients, including TSC2 and thereby preventing their ubiquitination and proteasomal degradation. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC1	NM_000368.5	c.149T>C	p.Leu50Pro	missense_variant	Exon 4 of 23	ENST00000298552.9	NP_000359.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC1	ENST00000298552.9	c.149T>C	p.Leu50Pro	missense_variant	Exon 4 of 23	1	NM_000368.5	ENSP00000298552.3
TSC1	ENST00000490179.4	c.149T>C	p.Leu50Pro	missense_variant	Exon 5 of 24	3		ENSP00000495533.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Tuberous sclerosis 1 Uncertain:1

Feb 05, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ClinVar contains an entry for this variant (Variation ID: 48793). This missense change has been observed in individual(s) with clinical features of tuberous sclerosis complex (PMID: 19747374, 22867869, 32555378). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 50 of the TSC1 protein (p.Leu50Pro). 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. Experimental studies have shown that this missense change affects TSC1 function (PMID: 19747374, 21309039). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). -

Tuberous sclerosis syndrome Other:1

-

Tuberous sclerosis database (TSC1)

Significance: not provided

Review Status: no classification provided

Collection Method: curation

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.45
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.83	D;.;D;.;D;.;D;.;.;.;.;.;.;.;.;.;.;D;.;.;.
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.90	.;D;D;D;.;.;.;D;D;.;D;.;.;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.54	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.87	D
MutationAssessor	Uncertain	2.5	M;M;M;.;M;.;M;.;.;M;.;.;.;.;.;.;.;.;.;.;.
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-4.7	D;D;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.
REVEL	Pathogenic	0.96
Sift	Uncertain	0.0010	D;D;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.
Sift4G	Uncertain	0.0020	D;D;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.
Polyphen		1.0	D;.;D;.;D;.;D;.;.;.;.;D;D;D;.;.;.;D;.;.;.
Vest4		0.96
MutPred		0.89		Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);Gain of loop (P = 0.0013);
MVP		0.98
MPC		1.7
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.93
gMVP		0.91

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: rs118203341; hg19: chr9-135802649;