rs118203368

Positions:

• chr9-132925600-A-G
• chr9-132925600-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2 PP2 PP3_Strong

The ENST00000298552.9(TSC1):​c.350T>C​(p.Leu117Pro) 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. 12/21 in silico tools predict a damaging 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. L117V) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TSC1 ENST00000298552.9 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1 O:1
• Conservation: PhyloP100: 9.10

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 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), TSC1. . Gene score misZ 2.3217 (greater than the threshold 3.09). Trascript score misZ 3.6986 (greater than threshold 3.09). GenCC has associacion of gene with lung lymphangioleiomyomatosis, tuberous sclerosis 1, tuberous sclerosis, tuberous sclerosis complex, lymphangioleiomyomatosis.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.99

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TSC1	NM_000368.5	c.350T>C	p.Leu117Pro	missense_variant	5/23	ENST00000298552.9	NP_000359.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TSC1	ENST00000298552.9	c.350T>C	p.Leu117Pro	missense_variant	5/23	1	NM_000368.5	ENSP00000298552	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Tuberous sclerosis syndrome Pathogenic:1 Other:1

not provided, no classification provided	curation	Tuberous sclerosis database (TSC1)	-	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen	Dec 10, 2024	- -

Tuberous sclerosis 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 18, 2019

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. This variant has been reported to affect TSC1 protein function (PMID: 18830229, 21309039, 29127155). This variant has been observed in individual(s) with tuberous sclerosis complex (PMID: 18830229). ClinVar contains an entry for this variant (Variation ID: 49027). This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with proline at codon 117 of the TSC1 protein (p.Leu117Pro). The leucine residue is highly conserved and there is a moderate physicochemical difference between leucine and proline. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.48
CADD	Pathogenic	29
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.86	D;D;.;D;.;D;.;.;.;.;.;.;.;D;.;.
Eigen	Pathogenic	0.87
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	.;D;D;.;.;.;D;D;.;.;D;D;D;D;D;D
M_CAP	Pathogenic	0.57	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.95	D
MutationAssessor	Uncertain	2.5	M;M;.;M;.;M;.;.;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-5.1	D;D;.;.;.;.;.;.;.;.;.;.;.;D;.;.
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0010	D;D;.;.;.;.;.;.;.;.;.;.;.;D;.;.
Sift4G	Pathogenic	0.0010	D;D;.;.;.;.;.;.;.;.;.;.;.;D;.;.
Polyphen		1.0	D;D;.;D;.;D;.;.;D;D;D;.;.;D;.;.
Vest4		0.98
MutPred		0.95		Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);Gain of loop (P = 0.002);
MVP		0.95
MPC		1.8
ClinPred		1.0	D
GERP RS		5.3
Varity_R		0.94
gMVP		0.93

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: rs118203368; hg19: chr9-135800987;