17-18274986-G-A

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PM2BP4_StrongBP6_Moderate

The NM_004618.5(TOP3A):​c.2828-6C>T variant causes a splice region, intron change. The variant allele was found at a frequency of 0.0000174 in 1,612,716 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 30)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

TOP3A
NM_004618.5 splice_region, intron

Scores

2
Splicing: ADA: 0.00008491
2

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: 3.66
Variant links:
Genes affected
TOP3A (HGNC:11992): (DNA topoisomerase III alpha) This gene encodes a DNA topoisomerase, an enzyme that controls and alters the topologic states of DNA during transcription. This enzyme catalyzes the transient breaking and rejoining of a single strand of DNA which allows the strands to pass through one another, thus reducing the number of supercoils and altering the topology of DNA. This enzyme forms a complex with BLM which functions in the regulation of recombination in somatic cells. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Mar 2016]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.75).
BP6
Variant 17-18274986-G-A is Benign according to our data. Variant chr17-18274986-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 3620964.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TOP3ANM_004618.5 linkc.2828-6C>T splice_region_variant, intron_variant Intron 18 of 18 ENST00000321105.10 NP_004609.1 Q13472-1
TOP3ANM_001320759.2 linkc.2543-6C>T splice_region_variant, intron_variant Intron 17 of 17 NP_001307688.1 Q13472-3
TOP3AXM_047436633.1 linkc.1907-6C>T splice_region_variant, intron_variant Intron 16 of 16 XP_047292589.1
TOP3AXM_047436634.1 linkc.1907-6C>T splice_region_variant, intron_variant Intron 16 of 16 XP_047292590.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TOP3AENST00000321105.10 linkc.2828-6C>T splice_region_variant, intron_variant Intron 18 of 18 1 NM_004618.5 ENSP00000321636.5 Q13472-1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152040
Hom.:
0
Cov.:
30
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000193
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000160
AC:
4
AN:
250040
Hom.:
0
AF XY:
0.0000148
AC XY:
2
AN XY:
135356
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000545
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000265
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000164
AC:
24
AN:
1460558
Hom.:
0
Cov.:
31
AF XY:
0.0000151
AC XY:
11
AN XY:
726606
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000189
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152158
Hom.:
0
Cov.:
30
AF XY:
0.0000134
AC XY:
1
AN XY:
74370
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000193
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000441
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000227
EpiCase
AF:
0.0000546
EpiControl
AF:
0.00

ClinVar

Significance: Likely benign
Submissions summary: Benign:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not provided Benign:1
Jul 21, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.75
CADD
Benign
13
DANN
Benign
0.45
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000085
dbscSNV1_RF
Benign
0.0060
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.

Other links and lift over

dbSNP: rs529791333; hg19: chr17-18178300; API