NM_000368.5:c.1178C>A

Variant names:

• chr9-132910656-G-T
• rs201452238
• NM_000368.5:c.1178C>A

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000368.5(TSC1):​c.1178C>A​(p.Thr393Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. T393I) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 31)
• Consequence: TSC1 NM_000368.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.37
• 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: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics, Genomics England PanelApp
• 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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC1	NM_000368.5	MANE Select	c.1178C>A	p.Thr393Asn	missense	Exon 12 of 23	NP_000359.1	Q92574-1
	TSC1	NM_001406592.1		c.1178C>A	p.Thr393Asn	missense	Exon 12 of 23	NP_001393521.1	X5D9D2
	TSC1	NM_001406593.1		c.1178C>A	p.Thr393Asn	missense	Exon 12 of 23	NP_001393522.1	Q92574-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC1	ENST00000298552.9	TSL:1 MANE Select	c.1178C>A	p.Thr393Asn	missense	Exon 12 of 23	ENSP00000298552.3	Q92574-1
	TSC1	ENST00000490179.4	TSL:3	c.1178C>A	p.Thr393Asn	missense	Exon 13 of 24	ENSP00000495533.2	Q92574-1
	TSC1	ENST00000493467.6	TSL:1	n.449C>A		non_coding_transcript_exon	Exon 4 of 4

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Tuberous sclerosis 1 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.52
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.060
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.48	T
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.78
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.86	D
M_CAP	Pathogenic	0.34	D
MetaRNN	Uncertain	0.61	D
MetaSVM	Uncertain	0.70	D
MutationAssessor	Uncertain	2.4	M
PhyloP100		7.4
PrimateAI	Uncertain	0.59	T
PROVEAN	Benign	-1.1	N
REVEL	Uncertain	0.59
Sift	Uncertain	0.014	D
Sift4G	Uncertain	0.0080	D
Polyphen		0.96	D
Vest4		0.70
MutPred		0.42		Loss of glycosylation at T393 (P = 6e-04)
MVP		0.83
MPC		1.5
ClinPred		0.87	D
GERP RS		5.8
Varity_R		0.20
gMVP		0.46
Mutation Taster		=65/35	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: rs201452238; hg19: chr9-135786043;