16-2072939-A-T

Variant names:

• chr16-2072939-A-T
• rs1555506986
• NM_000548.5:c.2311A>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.2311A>T​(p.Thr771Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,254 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. T771I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 9.02
• Publications: 0 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: PanelApp Australia, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp, 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 16-2072939-A-T is Benign according to our data. Variant chr16-2072939-A-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 467935.

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.2311A>T	p.Thr771Ser	missense	Exon 21 of 42	NP_000539.2
	TSC2	NM_001406663.1		c.2311A>T	p.Thr771Ser	missense	Exon 21 of 42	NP_001393592.1
	TSC2	NM_001114382.3		c.2311A>T	p.Thr771Ser	missense	Exon 21 of 41	NP_001107854.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TSC2	ENST00000219476.9	TSL:5 MANE Select	c.2311A>T	p.Thr771Ser	missense	Exon 21 of 42	ENSP00000219476.3
	TSC2	ENST00000350773.9	TSL:1	c.2311A>T	p.Thr771Ser	missense	Exon 21 of 41	ENSP00000344383.4
	TSC2	ENST00000401874.7	TSL:1	c.2311A>T	p.Thr771Ser	missense	Exon 21 of 40	ENSP00000384468.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461254 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 726898

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44718

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: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52802

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

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

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

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.21
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.14
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.54	D
Eigen	Uncertain	0.66
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.87	D
M_CAP	Uncertain	0.19	D
MetaRNN	Uncertain	0.73	D
MetaSVM	Uncertain	0.46	D
MutationAssessor	Benign	1.8	L
PhyloP100		9.0
PrimateAI	Uncertain	0.71	T
PROVEAN	Benign	-1.3	N
REVEL	Pathogenic	0.65
Sift	Uncertain	0.022	D
Sift4G	Uncertain	0.048	D
Polyphen		0.99	D
Vest4		0.64
MutPred		0.43		Loss of catalytic residue at T771 (P = 0.1301)
MVP		0.90
ClinPred		0.90	D
GERP RS		5.7
Varity_R		0.31
gMVP		0.50
Mutation Taster		=50/50

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: rs1555506986; hg19: chr16-2122940;