20-41123278-A-G

Variant names:

• chr20-41123278-A-G
• NM_003286.4:c.2279A>G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_003286.4(TOP1):​c.2279A>G​(p.Asp760Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,242 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: TOP1 NM_003286.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.22
• Publications: 0 publications found

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]

PLCG1-AS1 (HGNC:40450): (PLCG1 antisense RNA 1)

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.12219387).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003286.4. 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
	TOP1	NM_003286.4	MANE Select	c.2279A>G	p.Asp760Gly	missense	Exon 21 of 21	NP_003277.1	P11387
	PLCG1-AS1	NR_109889.1		n.710+10209T>C		intron	N/A

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TOP1	ENST00000361337.3	TSL:1 MANE Select	c.2279A>G	p.Asp760Gly	missense	Exon 21 of 21	ENSP00000354522.2	P11387
	PLCG1-AS1	ENST00000454626.1	TSL:1	n.713+10209T>C		intron	N/A
	TOP1	ENST00000680945.1		c.872A>G	p.Asp291Gly	missense	Exon 9 of 9	ENSP00000504935.1	A0A7P0T852

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461242 Hom.: 0 Cov.: 29 AF XY: 0.00000138 AC XY: 1 AN XY: 726966

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

American (AMR) AF: 0.00 AC: 0 AN: 44716

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39694

South Asian (SAS) AF: 0.00 AC: 0 AN: 86244

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

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

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111430

Other (OTH) AF: 0.00 AC: 0 AN: 60380

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	TOP1-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.092
BayesDel_addAF	Benign	-0.088	T
BayesDel_noAF	Benign	-0.36
CADD	Uncertain	23
DANN	Benign	0.96
DEOGEN2	Benign	0.32	T
Eigen	Benign	-0.054
Eigen_PC	Benign	0.19
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.90	D
M_CAP	Benign	0.010	T
MetaRNN	Benign	0.12	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.46	N
PhyloP100		9.2
PrimateAI	Benign	0.45	T
PROVEAN	Benign	-1.2	N
REVEL	Benign	0.15
Sift	Benign	0.43	T
Sift4G	Benign	0.44	T
Polyphen		0.0010	B
Vest4		0.22
MutPred		0.18		Gain of catalytic residue at A759 (P = 0.0885)
MVP		0.34
MPC		1.1
ClinPred		0.68	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.8
Varity_R		0.35
gMVP		0.83
Mutation Taster		=63/37	polymorphism

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

Other links and lift over

hg19: chr20-39751918;