16-2081646-C-T

Variant names:

• chr16-2081646-C-T
• rs45517305
• NM_000548.5:c.3662C>T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP6

The NM_000548.5(TSC2):​c.3662C>T​(p.Ser1221Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,460,586 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. S1221T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 7.84
• Publications: 10 publications found

Genes affected

TSC2 (HGNC:12363): (TSC complex subunit 2) This gene is a tumor suppressor gene that encodes the growth inhibitory protein tuberin. Tuberin interacts with hamartin to form the TSC protein complex which functions in the control of cell growth. This TSC protein complex negatively regulates mammalian target of rapamycin complex 1 (mTORC1) signaling which is a major regulator of anabolic cell growth. Mutations in this gene have been associated with tuberous sclerosis and lymphangioleiomyomatosis. [provided by RefSeq, May 2022]

TSC2 Gene-Disease associations (from GenCC):

• tuberous sclerosis

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• tuberous sclerosis 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, Ambry Genetics
• 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 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP6: Variant 16-2081646-C-T is Benign according to our data. Variant chr16-2081646-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 943389.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000548.5. 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
	TSC2	NM_000548.5	MANE Select	c.3662C>T	p.Ser1221Leu	missense	Exon 31 of 42	NP_000539.2	P49815-1
	TSC2	NM_001406663.1		c.3659C>T	p.Ser1220Leu	missense	Exon 31 of 42	NP_001393592.1	A0A2R8Y6C9
	TSC2	NM_001114382.3		c.3662C>T	p.Ser1221Leu	missense	Exon 31 of 41	NP_001107854.1	P49815-4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC2	ENST00000219476.9	TSL:5 MANE Select	c.3662C>T	p.Ser1221Leu	missense	Exon 31 of 42	ENSP00000219476.3	P49815-1
	TSC2	ENST00000350773.9	TSL:1	c.3662C>T	p.Ser1221Leu	missense	Exon 31 of 41	ENSP00000344383.4	P49815-4
	TSC2	ENST00000401874.7	TSL:1	c.3530C>T	p.Ser1177Leu	missense	Exon 30 of 40	ENSP00000384468.2	P49815-5

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1460586 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 726592

African (AFR) AF: 0.0000299 AC: 1 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44720

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

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

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52154

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111992

Other (OTH) AF: 0.00 AC: 0 AN: 60378

GnomAD4 genome Cov.: 34

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	-	Hereditary cancer-predisposing syndrome (1)
-	1	-	TSC2-related disorder (1)
-	-	1	Tuberous sclerosis 2 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.44
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.19
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.73	D
Eigen	Uncertain	0.60
Eigen_PC	Uncertain	0.54
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.44	D
MetaRNN	Uncertain	0.67	D
MetaSVM	Uncertain	0.74	D
MutationAssessor	Uncertain	2.4	M
PhyloP100		7.8
PrimateAI	Uncertain	0.74	T
PROVEAN	Uncertain	-2.9	D
REVEL	Pathogenic	0.69
Sift	Benign	0.068	T
Sift4G	Benign	0.17	T
Polyphen		1.0	D
Vest4		0.85
MutPred		0.28		Loss of disorder (P = 0.0075)
MVP		0.89
ClinPred		0.97	D
GERP RS		3.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.31
gMVP		0.54
Mutation Taster		=75/25	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs45517305; hg19: chr16-2131647; COSMIC: COSV54763808; COSMIC: COSV54763808;