6-16326468-C-T

Position:

chr6-16326468-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP3BS2

The NM_001128164.2(ATXN1):c.1843G>A(p.Val615Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000044 in 1,614,164 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000042 ( 0 hom. )

Consequence

ATXN1
NM_001128164.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.39

Variant links:

Genes affected

ATXN1 (HGNC:10548): (ataxin 1) 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. The function of the ataxins is not known. This locus has been mapped to chromosome 6, and it has been determined that the diseased allele contains 40-83 CAG repeats, compared to 6-39 in the normal allele, and is associated with spinocerebellar ataxia type 1 (SCA1). Alternative splicing results in multiple transcript variants, with one variant encoding multiple distinct proteins, ATXN1 and Alt-ATXN1, due to the use of overlapping alternate reading frames. [provided by RefSeq, Nov 2017]

ATXN1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.786

BS2

High AC in GnomAd4 at 9 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
ATXN1	NM_001128164.2 linkuse as main transcript	c.1843G>A	p.Val615Ile	missense_variant	7/8	ENST00000436367.6	NP_001121636.1
ATXN1	NM_000332.4 linkuse as main transcript	c.1843G>A	p.Val615Ile	missense_variant	8/9		NP_000323.2
ATXN1	NM_001357857.2 linkuse as main transcript	c.*1256G>A		3_prime_UTR_variant	8/9		NP_001344786.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
ATXN1	ENST00000436367.6 linkuse as main transcript	c.1843G>A	p.Val615Ile	missense_variant	7/8	1	NM_001128164.2	ENSP00000416360	P1	P54253-1
ATXN1	ENST00000244769.8 linkuse as main transcript	c.1843G>A	p.Val615Ile	missense_variant	8/9	1		ENSP00000244769	P1	P54253-1

Frequencies

GnomAD3 genomes

AF:

0.0000591

AC:

AN:

152188

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000415

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000882

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000318

AC:

AN:

251474

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135914

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:

0.0000653

Gnomad FIN exome

AF:

0.0000462

Gnomad NFE exome

AF:

0.0000440

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000424

AC:

AN:

1461858

Hom.:

Cov.:

AF XY:

0.0000399

AC XY:

AN XY:

727232

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000348

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.0000441

Gnomad4 OTH exome

AF:

0.000116

GnomAD4 genome

AF:

0.0000591

AC:

AN:

152306

Hom.:

Cov.:

AF XY:

0.0000806

AC XY:

AN XY:

74470

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000415

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000882

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000100

Hom.:

Bravo

AF:

0.0000189

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.0000545

EpiControl

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

Mar 21, 2023

The c.1843G>A (p.V615I) alteration is located in exon 8 (coding exon 1) of the ATXN1 gene. This alteration results from a G to A substitution at nucleotide position 1843, causing the valine (V) at amino acid position 615 to be replaced by an isoleucine (I). 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

Uncertain

0.45

BayesDel_addAF

Uncertain

0.030

BayesDel_noAF

Uncertain

-0.060

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.41

T;T

Eigen

Uncertain

0.58

Eigen_PC

Uncertain

0.53

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.96

.;D

M_CAP

Uncertain

0.14

MetaRNN

Pathogenic

0.79

D;D

MetaSVM

Uncertain

0.22

MutationAssessor

Uncertain

2.2

M;M

MutationTaster

Benign

1.0

D;D;D

PrimateAI

Uncertain

0.62

PROVEAN

Benign

-0.73

N;N

REVEL

Uncertain

0.58

Sift

Uncertain

0.015

D;D

Sift4G

Uncertain

0.030

D;D

Polyphen

0.96

D;D

Vest4

0.71

MutPred

0.64

Loss of sheet (P = 0.0817);Loss of sheet (P = 0.0817);

MVP

0.92

MPC

1.1

ClinPred

0.41

GERP RS

4.2

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.36

gMVP

0.41

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