chr9-132907371-C-A

Variant names:

• chr9-132907371-C-A
• rs1554816432
• NM_000368.5:c.1264-1G>T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_000368.5(TSC1):​c.1264-1G>T variant causes a splice acceptor, intron change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TSC1 NM_000368.5 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.09
• 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: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC1	NM_000368.5	MANE Select	c.1264-1G>T		splice_acceptor intron	N/A	NP_000359.1
	TSC1	NM_001406592.1		c.1264-1G>T		splice_acceptor intron	N/A	NP_001393521.1
	TSC1	NM_001406593.1		c.1264-1G>T		splice_acceptor intron	N/A	NP_001393522.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC1	ENST00000298552.9	TSL:1 MANE Select	c.1264-1G>T		splice_acceptor intron	N/A	ENSP00000298552.3
	TSC1	ENST00000490179.4	TSL:3	c.1264-1G>T		splice_acceptor intron	N/A	ENSP00000495533.2
	TSC1	ENST00000643875.1		c.1264-1G>T		splice_acceptor intron	N/A	ENSP00000495158.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.13
CADD	Pathogenic	31
DANN	Uncertain	0.99
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		4.1
GERP RS		5.5
PromoterAI		-0.031	Neutral
Mutation Taster		=1/99	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.88
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.40		Position offset: -5
DS_AL_spliceai		0.99		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1554816432; hg19: chr9-135782758; COSMIC: COSV100051608; COSMIC: COSV100051608;