20-41080168-G-A

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_003286.4(TOP1):​c.419G>A​(p.Arg140Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000282 in 1,596,966 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000030 ( 0 hom. )

Consequence

TOP1
NM_003286.4 missense

Scores

1
6
12

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 6.17
Variant links:
Genes affected
TOP1 (HGNC:11986): (DNA topoisomerase I) 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 altering the topology of DNA. This gene is localized to chromosome 20 and has pseudogenes which reside on chromosomes 1 and 22. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.13921025).
BS2
High AC in GnomAdExome4 at 44 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
TOP1NM_003286.4 linkuse as main transcriptc.419G>A p.Arg140Gln missense_variant 6/21 ENST00000361337.3 NP_003277.1 P11387Q9BVT2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
TOP1ENST00000361337.3 linkuse as main transcriptc.419G>A p.Arg140Gln missense_variant 6/211 NM_003286.4 ENSP00000354522.2 P11387
TOP1ENST00000681058.1 linkuse as main transcriptn.573G>A non_coding_transcript_exon_variant 6/20
TOP1ENST00000681113.1 linkuse as main transcriptn.419G>A non_coding_transcript_exon_variant 6/23 ENSP00000505788.1 A0A7P0T9R7
TOP1ENST00000681392.1 linkuse as main transcriptn.1539G>A non_coding_transcript_exon_variant 2/18

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152164
Hom.:
0
Cov.:
32
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:
0.000192
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:
0.0000327
AC:
8
AN:
244474
Hom.:
0
AF XY:
0.00000758
AC XY:
1
AN XY:
132012
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000331
Gnomad SAS exome
AF:
0.0000348
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000897
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000305
AC:
44
AN:
1444682
Hom.:
0
Cov.:
26
AF XY:
0.0000362
AC XY:
26
AN XY:
719160
show subpopulations
Gnomad4 AFR exome
AF:
0.0000303
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.000304
Gnomad4 SAS exome
AF:
0.0000712
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000200
Gnomad4 OTH exome
AF:
0.0000502
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152284
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74462
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:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000189
ExAC
AF:
0.0000494
AC:
6

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsOct 21, 2024The c.419G>A (p.R140Q) alteration is located in exon 6 (coding exon 6) of the TOP1 gene. This alteration results from a G to A substitution at nucleotide position 419, causing the arginine (R) at amino acid position 140 to be replaced by a glutamine (Q). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.099
BayesDel_addAF
Benign
-0.30
T
BayesDel_noAF
Benign
-0.36
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Benign
0.17
T
Eigen
Uncertain
0.65
Eigen_PC
Pathogenic
0.67
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.94
D
M_CAP
Benign
0.018
T
MetaRNN
Benign
0.14
T
MetaSVM
Benign
-1.1
T
MutationAssessor
Uncertain
2.2
M
PrimateAI
Uncertain
0.57
T
PROVEAN
Benign
-0.47
N
REVEL
Benign
0.11
Sift
Benign
0.038
D
Sift4G
Benign
0.52
T
Polyphen
0.98
D
Vest4
0.34
MVP
0.32
MPC
0.91
ClinPred
0.21
T
GERP RS
5.6
Varity_R
0.19
gMVP
0.27

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.

Other links and lift over

dbSNP: rs183058581; hg19: chr20-39708808; API