9-132927229-A-G

Position:

• chr9-132927229-A-G

Variant summary

Our verdict is Pathogenic. Variant got 17 ACMG points: 17P and 0B. PM2 PM5 PP2 PP3_Strong PP5_Very_Strong

The NM_000368.5(TSC1):​c.182T>C​(p.Leu61Pro) 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 Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L61R) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TSC1 NM_000368.5 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2 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 Pathogenic. Variant got 17 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr9-132927229-A-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 64752.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP2: Missense variant where missense usually causes diseases, TSC1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.99
• PP5: Variant 9-132927229-A-G is Pathogenic according to our data. Variant chr9-132927229-A-G is described in ClinVar as [Pathogenic]. Clinvar id is 48842.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-132927229-A-G is described in Lovd as [Pathogenic]. Variant chr9-132927229-A-G is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TSC1	NM_000368.5	c.182T>C	p.Leu61Pro	missense_variant	4/23	ENST00000298552.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC1	ENST00000298552.9	c.182T>C	p.Leu61Pro	missense_variant	4/23	1	NM_000368.5	P4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Mar 31, 2022

Published functional studies suggest this variant disrupts TSC1-TSC2 complex function and results in decreased levels of TSC1 and increased mTOR activity (Hoogeveen-Westerveld et al., 2011; Mozaffari et al., 2009); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 23857276, 19747374, 21309039, 22867869) -

Tuberous sclerosis 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Feb 15, 2021

For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Leu61 amino acid residue in TSC1. Other variant(s) that disrupt this residue have been determined to be pathogenic (Invitae). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. Experimental studies have shown that this variant affects TSC1 protein function ‚Äã(PMID: 19747374) This variant has been observed in individual(s) with tuberous sclerosis complex (PMID: 19747374). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 48842). This variant is not present in population databases (ExAC no frequency). This sequence change replaces leucine with proline at codon 61 of the TSC1 protein (p.Leu61Pro). The leucine residue is highly conserved and there is a moderate physicochemical difference between leucine and proline. -

Tuberous sclerosis syndrome Other:1

not provided, no classification provided

curation

Tuberous sclerosis database (TSC1)

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.87	D;.;D;.;D;.;D;.;.;.;.;.;.;.;.;.;.;D;.;.;.
Eigen	Pathogenic	0.89
Eigen_PC	Pathogenic	0.84
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.71	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.5	M;M;M;.;M;.;M;.;.;M;.;.;.;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.72	T
PROVEAN	Pathogenic	-6.0	D;D;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;D;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.
Sift4G	Pathogenic	0.0	D;D;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.
Polyphen		1.0	D;.;D;.;D;.;D;.;.;.;.;D;D;D;.;.;.;D;.;.;.
Vest4		1.0
MutPred		0.94		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		0.96
MPC		1.8
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.96
gMVP		0.94

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: rs118203345; hg19: chr9-135802616; COSMIC: COSV53766305; COSMIC: COSV53766305;