chr16-2088275-C-G

Position:

• chr16-2088275-C-G

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 2P and 7B. PM1 BP4_Moderate BP6 BS2

The NM_000548.5(TSC2):​c.5209C>G​(p.Pro1737Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000685 in 1,460,404 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 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. P1737L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: TSC2 NM_000548.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 6.20

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]

ACMG classification

Verdict is Likely_benign. Variant got -5 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 7 benign, 15 uncertain in NM_000548.5
• BP4: Computational evidence support a benign effect (MetaRNN=0.20902684).
• BP6: Variant 16-2088275-C-G is Benign according to our data. Variant chr16-2088275-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 825547.We mark this variant Likely_benign, oryginal submissions are: {Benign=1, Uncertain_significance=1}.
• BS2: High AC in GnomAdExome4 at 10 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TSC2	NM_000548.5	c.5209C>G	p.Pro1737Ala	missense_variant	41/42	ENST00000219476.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TSC2	ENST00000219476.9	c.5209C>G	p.Pro1737Ala	missense_variant	41/42	5	NM_000548.5

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250534 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135752

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000885

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000685 AC: 10 AN: 1460404 Hom.: 0 Cov.: 35 AF XY: 0.00000413 AC XY: 3 AN XY: 726476

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000899

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Nov 13, 2019

The p.P1737A variant (also known as c.5209C>G), located in coding exon 40 of the TSC2 gene, results from a C to G substitution at nucleotide position 5209. The proline at codon 1737 is replaced by alanine, an amino acid with highly similar properties. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Tuberous sclerosis 2 Benign:1

Benign, criteria provided, single submitter

clinical testing

Invitae

Aug 30, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.070
CADD	Uncertain	25
DANN	Benign	0.94
DEOGEN2	Benign	0.34	T;.;.;.;.;.;.;.;.;.;.;.;T;.;T
Eigen	Benign	-0.12
Eigen_PC	Benign	0.037
FATHMM_MKL	Benign	0.76	D
LIST_S2	Uncertain	0.93	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.34	D
MetaRNN	Benign	0.21	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Uncertain	0.32	D
MutationAssessor	Benign	-0.63	N;.;.;.;.;.;.;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.59	T
PROVEAN	Benign	0.76	N;.;.;N;.;N;.;.;N;N;.;.;.;.;N
REVEL	Uncertain	0.63
Sift	Benign	1.0	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Sift4G	Benign	1.0	T;.;.;T;.;T;.;.;T;T;.;.;.;.;T
Polyphen		0.60	P;.;.;.;B;B;.;.;D;B;.;.;.;.;.
Vest4		0.39
MutPred		0.51		Gain of helix (P = 0.027);.;.;.;.;.;.;.;.;.;.;.;.;.;.;
MVP		0.81
ClinPred		0.39	T
GERP RS		4.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.18
gMVP		0.28

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs780112037; hg19: chr16-2138276;