3-63912764-C-T

Position:

chr3-63912764-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001377405.1(ATXN7):c.166C>T(p.Arg56Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000368 in 1,358,088 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000025 ( 0 hom. )

Consequence

ATXN7
NM_001377405.1 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.23

Variant links:

Genes affected

ATXN7 (HGNC:10560): (ataxin 7) The autosomal dominant cerebellar ataxias (ADCA) are a heterogeneous group of neurodegenerative disorders characterized by progressive degeneration of the cerebellum, brain stem and spinal cord. Clinically, ADCA has been divided into three groups: ADCA types I-III. ADCAI is genetically heterogeneous, with five genetic loci, designated spinocerebellar ataxia (SCA) 1, 2, 3, 4 and 6, being assigned to five different chromosomes. ADCAII, which always presents with retinal degeneration (SCA7), and ADCAIII often referred to as the 'pure' cerebellar syndrome (SCA5), are most likely homogeneous disorders. Several SCA genes have been cloned and shown to contain CAG repeats in their coding regions. ADCA is caused by the expansion of the CAG repeats, producing an elongated polyglutamine tract in the corresponding protein. The expanded repeats are variable in size and unstable, usually increasing in size when transmitted to successive generations. This locus has been mapped to chromosome 3, and it has been determined that the diseased allele associated with spinocerebellar ataxia-7 contains 37-306 CAG repeats (near the N-terminus), compared to 4-35 in the normal allele. The encoded protein is a component of the SPT3/TAF9/GCN5 acetyltransferase (STAGA) and TBP-free TAF-containing (TFTC) chromatin remodeling complexes, and it thus plays a role in transcriptional regulation. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2016]

ATXN7 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.20985925).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
ATXN7	NM_001377405.1 link	c.166C>T	p.Arg56Trp	missense_variant	3/13	ENST00000674280.1	NP_001364334.1
ATXN7	NM_001177387.1 link	c.166C>T	p.Arg56Trp	missense_variant	2/13		NP_001170858.1	O15265-2
ATXN7	NM_000333.4 link	c.166C>T	p.Arg56Trp	missense_variant	3/13		NP_000324.1	O15265-1Q9UPD8
ATXN7	NM_001377406.1 link	c.166C>T	p.Arg56Trp	missense_variant	2/12		NP_001364335.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ATXN7	ENST00000674280.1 link	c.166C>T	p.Arg56Trp	missense_variant	3/13		NM_001377405.1	ENSP00000501377.1		O15265-1

Frequencies

GnomAD3 genomes

AF:

0.0000133

AC:

AN:

150418

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:

0.0000297

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

0.00000248

AC:

AN:

1207670

Hom.:

Cov.:

AF XY:

0.00000339

AC XY:

AN XY:

589188

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:

0.00000202

Gnomad4 OTH exome

AF:

0.0000207

GnomAD4 genome

AF:

0.0000133

AC:

AN:

150418

Hom.:

Cov.:

AF XY:

0.0000136

AC XY:

AN XY:

73350

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:

0.0000297

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 26, 2024

The c.166C>T (p.R56W) alteration is located in exon 2 (coding exon 1) of the ATXN7 gene. This alteration results from a C to T substitution at nucleotide position 166, causing the arginine (R) at amino acid position 56 to be replaced by a tryptophan (W). 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

0.34

BayesDel_addAF

Benign

-0.089

BayesDel_noAF

Benign

-0.37

CADD

Uncertain

DANN

Uncertain

0.99

DEOGEN2

Benign

0.091

.;T;.;T;.

Eigen

Benign

-0.12

Eigen_PC

Benign

-0.24

FATHMM_MKL

Benign

0.68

LIST_S2

Benign

0.59

T;T;T;.;.

M_CAP

Benign

0.039

MetaRNN

Benign

0.21

T;T;T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

0.55

.;N;N;N;N

PrimateAI

Pathogenic

0.89

PROVEAN

Benign

-0.42

.;N;N;N;.

REVEL

Benign

0.054

Sift

Uncertain

0.0030

.;D;D;D;.

Sift4G

Uncertain

0.025

.;D;D;D;.

Polyphen

1.0, 1.0

.;D;D;D;D

Vest4

0.30, 0.27

MutPred

0.25

Loss of solvent accessibility (P = 6e-04);Loss of solvent accessibility (P = 6e-04);Loss of solvent accessibility (P = 6e-04);Loss of solvent accessibility (P = 6e-04);Loss of solvent accessibility (P = 6e-04);

MVP

0.21

ClinPred

0.87

GERP RS

2.2

Varity_R

0.21

gMVP

0.39

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.

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