3-25598334-A-T

Variant names:

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_StrongBS2

The NM_001330700.2(TOP2B):c.4854T>A(p.Asp1618Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000807 in 1,610,290 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000069 ( 0 hom. )

Consequence

TOP2B
NM_001330700.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -1.03

Variant links:

Genes affected

TOP2B (HGNC:11990): (DNA topoisomerase II beta) This gene encodes a DNA topoisomerase, an enzyme that controls and alters the topologic states of DNA during transcription. This nuclear enzyme is involved in processes such as chromosome condensation, chromatid separation, and the relief of torsional stress that occurs during DNA transcription and replication. It catalyzes the transient breaking and rejoining of two strands of duplex DNA which allows the strands to pass through one another, thus altering the topology of DNA. Two forms of this enzyme exist as likely products of a gene duplication event. The gene encoding this form, beta, is localized to chromosome 3 and the alpha form is localized to chromosome 17. The gene encoding this enzyme functions as the target for several anticancer agents and a variety of mutations in this gene have been associated with the development of drug resistance. Reduced activity of this enzyme may also play a role in ataxia-telangiectasia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2016]

TOP2B links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -8 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.022787035).

BS2

High AC in GnomAdExome4 at 10 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TOP2B	NM_001330700.2 link	c.4854T>A	p.Asp1618Glu	missense_variant	Exon 36 of 36	ENST00000264331.9	NP_001317629.1	Q02880-1
TOP2B	NM_001068.3 link	c.4839T>A	p.Asp1613Glu	missense_variant	Exon 36 of 36		NP_001059.2	Q02880-2Q59H80
TOP2B	XM_011534057.4 link	c.4743T>A	p.Asp1581Glu	missense_variant	Exon 35 of 35		XP_011532359.1
TOP2B	XM_047448821.1 link	c.4728T>A	p.Asp1576Glu	missense_variant	Exon 35 of 35		XP_047304777.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TOP2B	ENST00000264331.9 link	c.4854T>A	p.Asp1618Glu	missense_variant	Exon 36 of 36	5	NM_001330700.2	ENSP00000264331.4		Q02880-1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152238

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000385

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

GnomAD3 exomes

AF:

0.0000325

AC:

AN:

245914

Hom.:

AF XY:

0.0000375

AC XY:

AN XY:

133318

show subpopulations

Gnomad AFR exome

AF:

0.0000648

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000392

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000686

AC:

AN:

1458052

Hom.:

Cov.:

AF XY:

0.00000966

AC XY:

AN XY:

724984

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000454

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000101

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000180

Gnomad4 OTH exome

AF:

0.0000332

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152238

Hom.:

Cov.:

AF XY:

0.0000403

AC XY:

AN XY:

74374

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000385

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000189

ESP6500AA

AF:

0.000267

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000579

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Nov 27, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces aspartic acid, which is acidic and polar, with glutamic acid, which is acidic and polar, at codon 1613 of the TOP2B protein (p.Asp1613Glu). This variant is present in population databases (rs374745650, gnomAD 0.05%). This variant has not been reported in the literature in individuals affected with TOP2B-related conditions. An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Benign". The glutamic acid amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.089

BayesDel_addAF

Benign

-0.52

BayesDel_noAF

Benign

-0.66

CADD

Benign

0.0060

DANN

Benign

0.28

DEOGEN2

Benign

0.20

T;.

Eigen

Benign

-2.4

Eigen_PC

Benign

-2.3

FATHMM_MKL

Benign

0.080

LIST_S2

Benign

0.43

T;T

M_CAP

Benign

0.040

MetaRNN

Benign

0.023

T;T

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.0

N;.

PrimateAI

Uncertain

0.51

PROVEAN

Benign

-0.46

N;N

REVEL

Benign

0.058

Sift

Benign

0.70

T;T

Sift4G

Benign

0.097

T;T

Polyphen

0.0010

B;B

Vest4

0.21

MutPred

0.18

Gain of glycosylation at S1613 (P = 0.0068);.;

MVP

0.44

MPC

0.047

ClinPred

0.017

GERP RS

-0.47

Varity_R

0.017

gMVP

0.039

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over