chr9-32552432-A-G

Position:

chr9-32552432-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PVS1_ModeratePM2

The NM_005802.5(TOPORS):c.3+2T>C variant causes a splice donor change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,609,178 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

TOPORS
NM_005802.5 splice_donor

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.87

Variant links:

Genes affected

TOPORS (HGNC:21653): (TOP1 binding arginine/serine rich protein, E3 ubiquitin ligase) This gene encodes a nuclear protein which is serine and arginine rich, and contains a RING-type zinc finger domain. It is highly expressed in the testis, and functions as an ubiquitin-protein E3 ligase. Mutations in this gene are associated with retinitis pigmentosa type 31. Alternatively spliced transcript variants, encoding different isoforms, have been observed for this locus. [provided by RefSeq, Sep 2010]

TOPORS links:

SMIM27 (HGNC:31420): (small integral membrane protein 27) Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

SMIM27 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.048438497 fraction of the gene.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TOPORS	NM_005802.5 linkuse as main transcript	c.3+2T>C		splice_donor_variant		ENST00000360538.7	NP_005793.2
SMIM27	NM_001387564.1 linkuse as main transcript	c.-3A>G		5_prime_UTR_variant	1/2	ENST00000692500.1	NP_001374493.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TOPORS	ENST00000360538.7 linkuse as main transcript	c.3+2T>C		splice_donor_variant		1	NM_005802.5	ENSP00000353735	P3	Q9NS56-1
SMIM27	ENST00000692500.1 linkuse as main transcript	c.-3A>G		5_prime_UTR_variant	1/2		NM_001387564.1	ENSP00000508648	P1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152182

Hom.:

Cov.:

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:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000417

AC:

AN:

239534

Hom.:

AF XY:

0.00

AC XY:

AN XY:

130294

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000929

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.86e-7

AC:

AN:

1456996

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

724274

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

9.01e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152182

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74334

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000480

Hom.:

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Nov 28, 2023

This sequence change affects a donor splice site in intron 1 of the TOPORS gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), however the current clinical and genetic evidence is not sufficient to establish whether loss-of-function variants in TOPORS cause disease. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with TOPORS-related conditions. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.25

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Pathogenic

0.95

Eigen_PC

Pathogenic

0.78

FATHMM_MKL

Benign

0.35

MutationTaster

Benign

1.0

D;D

GERP RS

5.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

2.7

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.91

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.22

Position offset: -50

DS_DL_spliceai

0.91

Position offset: 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