chr9-132921910-A-G

Variant names:

• chr9-132921910-A-G
• rs118203403
• NM_000368.5:c.572T>C

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Moderate

The NM_000368.5(TSC1):​c.572T>C​(p.Leu191Pro) 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. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L191F) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: TSC1 NM_000368.5 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.32
• Publications: 3 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 12 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 27 uncertain in NM_000368.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr9-132921910-A-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 49060.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985
• PP5: Variant 9-132921910-A-G is Pathogenic according to our data. Variant chr9-132921910-A-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 421409.Status of the report is criteria_provided_single_submitter, 1 stars.

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.572T>C	p.Leu191Pro	missense	Exon 7 of 23	NP_000359.1
	TSC1	NM_001406592.1		c.572T>C	p.Leu191Pro	missense	Exon 7 of 23	NP_001393521.1
	TSC1	NM_001406593.1		c.572T>C	p.Leu191Pro	missense	Exon 7 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.572T>C	p.Leu191Pro	missense	Exon 7 of 23	ENSP00000298552.3
	TSC1	ENST00000490179.4	TSL:3	c.572T>C	p.Leu191Pro	missense	Exon 8 of 24	ENSP00000495533.2
	TSC1	ENST00000403810.6	TSL:1	c.572T>C	p.Leu191Pro	missense	Exon 7 of 10	ENSP00000386093.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Jun 23, 2016

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The L191P variant has not been published as a pathogenic variant, nor has it been reported as a benign variant to our knowledge. It was not observed in approximately 6,500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. The L191P variant is a semi-conservative amino acid substitution, which may impact secondary protein structure as these residues differ in some properties. This substitution occurs at a position that is conserved across species and in silico analysis predicts this variant is probably damaging to the protein structure/function. Missense variants in nearby residues (L191H/R, R190P) have been reported in the Human Gene Mutation Database in association with tuberous sclerosis complex (Stenson et al., 2014), supporting the functional importance of this region of the protein. Therefore, this variant is likely pathogenic; however, the possibility that it is benign cannot be excluded.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.87	D
Eigen	Pathogenic	0.95
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.93	D
M_CAP	Pathogenic	0.67	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.5	M
PhyloP100		9.3
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-6.5	D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		1.0
MutPred		0.91		Loss of stability (P = 0.0214)
MVP		0.99
MPC		1.8
ClinPred		1.0	D
GERP RS		6.1
Varity_R		0.96
gMVP		0.98
Mutation Taster		=7/93	disease causing (ClinVar)

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: rs118203403; hg19: chr9-135797297;