NM_001330700.2:c.4805G>C

Variant names:

• chr3-25598383-C-G
• rs1449475384
• NM_001330700.2:c.4805G>C

Variant summary

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

The NM_001330700.2(TOP2B):​c.4805G>C​(p.Arg1602Pro) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,192 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 (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: TOP2B NM_001330700.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.38
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• B-cell immunodeficiency, distal limb anomalies, and urogenital malformations

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: ClinGen, Illumina, Ambry Genetics, PanelApp Australia
• neurodevelopmental disorder

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics

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, 0.811

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001330700.2. 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
	TOP2B	NM_001330700.2	MANE Select	c.4805G>C	p.Arg1602Pro	missense	Exon 36 of 36	NP_001317629.1	Q02880-1
	TOP2B	NM_001068.3		c.4790G>C	p.Arg1597Pro	missense	Exon 36 of 36	NP_001059.2	Q59H80

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TOP2B	ENST00000264331.9	TSL:5 MANE Select	c.4805G>C	p.Arg1602Pro	missense	Exon 36 of 36	ENSP00000264331.4	Q02880-1
	TOP2B	ENST00000435706.7	TSL:1	c.4790G>C	p.Arg1597Pro	missense	Exon 36 of 36	ENSP00000396704.2
	TOP2B	ENST00000424225.2	TSL:1	c.4706G>C	p.Arg1569Pro	missense	Exon 36 of 36	ENSP00000391112.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461192 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726852

African (AFR) AF: 0.00 AC: 0 AN: 33468

American (AMR) AF: 0.00 AC: 0 AN: 44690

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26122

East Asian (EAS) AF: 0.00 AC: 0 AN: 39666

South Asian (SAS) AF: 0.00 AC: 0 AN: 86188

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53382

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111576

Other (OTH) AF: 0.00 AC: 0 AN: 60334

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.18	D
BayesDel_noAF	Uncertain	0.020
CADD	Pathogenic	28
DANN	Uncertain	0.99
DEOGEN2	Benign	0.39	T
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.65
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D
M_CAP	Benign	0.083	D
MetaRNN	Pathogenic	0.81	D
MetaSVM	Benign	-0.32	T
MutationAssessor	Benign	0.90	L
PhyloP100		6.4
PrimateAI	Uncertain	0.78	T
PROVEAN	Uncertain	-3.2	D
REVEL	Uncertain	0.56
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.021	D
Polyphen		1.0	D
Vest4		0.58
MutPred		0.78		Gain of glycosylation at T1600 (P = 0.0069)
MVP		0.45
MPC		0.39
ClinPred		0.95	D
GERP RS		5.6
Varity_R		0.81
gMVP		0.54
Mutation Taster		=37/63	disease causing

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: rs1449475384; hg19: chr3-25639874;