16-2071828-C-G

Variant names:

• chr16-2071828-C-G
• rs991714565
• NM_000548.5:c.1991C>G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000548.5(TSC2):​c.1991C>G​(p.Ser664Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000188 in 1,597,966 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 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. S664F) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 5.63
• Publications: 1 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 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.829

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.1991C>G	p.Ser664Cys	missense	Exon 19 of 42	NP_000539.2	P49815-1
	TSC2	NM_001406663.1		c.1991C>G	p.Ser664Cys	missense	Exon 19 of 42	NP_001393592.1	A0A2R8Y6C9
	TSC2	NM_001114382.3		c.1991C>G	p.Ser664Cys	missense	Exon 19 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.1991C>G	p.Ser664Cys	missense	Exon 19 of 42	ENSP00000219476.3	P49815-1
	TSC2	ENST00000350773.9	TSL:1	c.1991C>G	p.Ser664Cys	missense	Exon 19 of 41	ENSP00000344383.4	P49815-4
	TSC2	ENST00000401874.7	TSL:1	c.1991C>G	p.Ser664Cys	missense	Exon 19 of 40	ENSP00000384468.2	P49815-5

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152072 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1445894 Hom.: 0 Cov.: 32 AF XY: 0.00000139 AC XY: 1 AN XY: 717852

African (AFR) AF: 0.00 AC: 0 AN: 33116

American (AMR) AF: 0.0000231 AC: 1 AN: 43228

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25716

East Asian (EAS) AF: 0.00 AC: 0 AN: 38964

South Asian (SAS) AF: 0.00 AC: 0 AN: 83612

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50850

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5744

European-Non Finnish (NFE) AF: 9.05e-7 AC: 1 AN: 1104974

Other (OTH) AF: 0.00 AC: 0 AN: 59690

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152072 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74280

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41424

American (AMR) AF: 0.0000654 AC: 1 AN: 15280

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5172

South Asian (SAS) AF: 0.00 AC: 0 AN: 4824

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 67960

Other (OTH) AF: 0.00 AC: 0 AN: 2088

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Hereditary cancer-predisposing syndrome (1)
-	1	-	Lymphangiomyomatosis;C1846385:Isolated focal cortical dysplasia type II;C1860707:Tuberous sclerosis 2 (1)
-	1	-	Tuberous sclerosis 2 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.27
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.23
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.78	D
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D
M_CAP	Pathogenic	0.32	D
MetaRNN	Pathogenic	0.83	D
MetaSVM	Uncertain	0.78	D
MutationAssessor	Uncertain	2.4	M
PhyloP100		5.6
PrimateAI	Uncertain	0.65	T
PROVEAN	Uncertain	-3.2	D
REVEL	Pathogenic	0.66
Sift	Uncertain	0.012	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.58
MutPred		0.38		Loss of phosphorylation at S664 (P = 0.0069)
MVP		0.87
ClinPred		0.94	D
GERP RS		5.5
Varity_R		0.31
gMVP		0.60
Mutation Taster		=56/44	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: rs991714565; hg19: chr16-2121829;