9-132903748-T-G

Variant names:

• chr9-132903748-T-G
• rs752054698
• NM_000368.5:c.2111A>C

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000368.5(TSC1):​c.2111A>C​(p.Tyr704Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,494 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. Y704C) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TSC1 NM_000368.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 5.06
• Publications: 0 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: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.873

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000368.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC1	NM_000368.5	MANE Select	c.2111A>C	p.Tyr704Ser	missense	Exon 17 of 23	NP_000359.1
	TSC1	NM_001406592.1		c.2111A>C	p.Tyr704Ser	missense	Exon 17 of 23	NP_001393521.1
	TSC1	NM_001406593.1		c.2111A>C	p.Tyr704Ser	missense	Exon 17 of 23	NP_001393522.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC1	ENST00000298552.9	TSL:1 MANE Select	c.2111A>C	p.Tyr704Ser	missense	Exon 17 of 23	ENSP00000298552.3
	TSC1	ENST00000490179.4	TSL:3	c.2111A>C	p.Tyr704Ser	missense	Exon 18 of 24	ENSP00000495533.2
	TSC1	ENST00000643875.1		c.2111A>C	p.Tyr704Ser	missense	Exon 17 of 23	ENSP00000495158.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461494 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727036

African (AFR) AF: 0.00 AC: 0 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86234

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5440

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1112004

Other (OTH) AF: 0.00 AC: 0 AN: 60368

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Tuberous sclerosis 1 Uncertain:1

May 10, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. 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: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with TSC1-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces tyrosine with serine at codon 704 of the TSC1 protein (p.Tyr704Ser). The tyrosine residue is highly conserved and there is a large physicochemical difference between tyrosine and serine.

Hereditary cancer-predisposing syndrome Uncertain:1

Dec 19, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Y704S variant (also known as c.2111A>C), located in coding exon 15 of the TSC1 gene, results from an A to C substitution at nucleotide position 2111. The tyrosine at codon 704 is replaced by serine, an amino acid with dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.93
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.40
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.83	D
Eigen	Uncertain	0.54
Eigen_PC	Uncertain	0.45
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.94	D
M_CAP	Pathogenic	0.38	D
MetaRNN	Pathogenic	0.87	D
MetaSVM	Uncertain	0.74	D
MutationAssessor	Uncertain	2.5	M
PhyloP100		5.1
PrimateAI	Uncertain	0.75	T
PROVEAN	Pathogenic	-7.5	D
REVEL	Pathogenic	0.78
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.93
MutPred		0.68		Gain of disorder (P = 0.0019)
MVP		0.95
MPC		1.7
ClinPred		1.0	D
GERP RS		4.2
Varity_R		0.89
gMVP		0.65
Mutation Taster		=68/32	polymorphism

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: rs752054698; hg19: chr9-135779135;