9-132923383-A-G

Variant names:

• chr9-132923383-A-G
• rs118203385
• NM_000368.5:c.473T>C

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_000368.5(TSC1):​c.473T>C​(p.Phe158Ser) 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. F158C) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TSC1 NM_000368.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:1 O:1
• Conservation: PhyloP100: 8.70
• Publications: 8 publications found

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]

TSC1 Gene-Disease associations (from GenCC):

• tuberous sclerosis

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• tuberous sclerosis 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, PanelApp Australia, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae)
• lung lymphangioleiomyomatosis

  Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp
• tuberous sclerosis complex

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 31 uncertain in NM_000368.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.981
• PP5: Variant 9-132923383-A-G is Pathogenic according to our data. Variant chr9-132923383-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 64837.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TSC1	NM_000368.5	c.473T>C	p.Phe158Ser	missense_variant	Exon 6 of 23	ENST00000298552.9	NP_000359.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TSC1	ENST00000298552.9	c.473T>C	p.Phe158Ser	missense_variant	Exon 6 of 23	1	NM_000368.5	ENSP00000298552.3
TSC1	ENST00000490179.4	c.473T>C	p.Phe158Ser	missense_variant	Exon 7 of 24	3		ENSP00000495533.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:2 Uncertain:1 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:2

Apr 18, 2023

Mayo Clinic Laboratories, Mayo Clinic

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

PP3, PP4, PM2, PS3 -

Dec 27, 2022

Athena Diagnostics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant has been identified in at least one individual with clinical features associated with this gene. This variant has not been reported in large, multi-ethnic general populations (http://gnomad.broadinstitute.org). Assessment of experimental evidence suggests this variant results in abnormal protein function. (PMID: 22161988) -

Tuberous sclerosis 1 Uncertain:1

Oct 30, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces phenylalanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 158 of the TSC1 protein (p.Phe158Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of tuberous sclerosis complex (PMID: 22161988; internal data). ClinVar contains an entry for this variant (Variation ID: 64837). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt TSC1 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects TSC1 function (PMID: 22161988). 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. -

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	0.99
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.46
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.86	D;.;D;.;D;.;D;.;.;.;.;.;.;.;.;.;.;D;.;.
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	.;D;D;D;.;.;.;D;D;.;D;.;.;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.60	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
MetaSVM	Pathogenic	0.96	D
MutationAssessor	Uncertain	2.5	M;.;M;.;M;.;M;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100		8.7
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-7.3	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		0.99
MutPred		0.90		Loss of helix (P = 0.0093);.;Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);.;.;Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);Loss of helix (P = 0.0093);.;Loss of helix (P = 0.0093);.;Loss of helix (P = 0.0093);
MVP		0.98
MPC		1.9
ClinPred		1.0	D
GERP RS		5.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.93
gMVP		0.83
Mutation Taster		=0/100	disease causing

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

Other links and lift over

dbSNP: rs118203385; hg19: chr9-135798770;