3-63912699-A-C

Variant summary

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

The NM_001377405.1(ATXN7):c.101A>C(p.Gln34Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000129 in 1,173,338 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q34P?) has been classified as Benign.

Frequency

Genomes: 𝑓 0.000089 ( 0 hom., cov: 31)

Exomes 𝑓: 0.00013 ( 1 hom. )

Consequence

ATXN7
NM_001377405.1 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.625

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 Likely_benign. Variant got -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.080055594).

BS2

High AC in GnomAd at 13 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
ATXN7	NM_001377405.1 linkuse as main transcript	c.101A>C	p.Gln34Pro	missense_variant	3/13	ENST00000674280.1
ATXN7	NM_001177387.1 linkuse as main transcript	c.101A>C	p.Gln34Pro	missense_variant	2/13
ATXN7	NM_000333.4 linkuse as main transcript	c.101A>C	p.Gln34Pro	missense_variant	3/13
ATXN7	NM_001377406.1 linkuse as main transcript	c.101A>C	p.Gln34Pro	missense_variant	2/12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ATXN7	ENST00000674280.1 linkuse as main transcript	c.101A>C	p.Gln34Pro	missense_variant	3/13		NM_001377405.1	P2	O15265-1

Frequencies

GnomAD3 genomes

AF:

0.0000888

AC:

AN:

146350

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000125

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000677

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000211

Gnomad FIN

AF:

0.000111

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000604

Gnomad OTH

AF:

0.000496

GnomAD3 exomes

AF:

0.0000769

AC:

AN:

26008

Hom.:

AF XY:

0.000138

AC XY:

AN XY:

14460

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:

0.000515

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000134

AC:

138

AN:

1026882

Hom.:

Cov.:

AF XY:

0.000149

AC XY:

AN XY:

490648

show subpopulations

Gnomad4 AFR exome

AF:

0.000103

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000615

Gnomad4 SAS exome

AF:

0.0000831

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000136

Gnomad4 OTH exome

AF:

0.000264

GnomAD4 genome

AF:

0.0000888

AC:

AN:

146456

Hom.:

Cov.:

AF XY:

0.0000701

AC XY:

AN XY:

71300

show subpopulations

Gnomad4 AFR

AF:

0.000125

Gnomad4 AMR

AF:

0.0000676

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000211

Gnomad4 FIN

AF:

0.000111

Gnomad4 NFE

AF:

0.0000604

Gnomad4 OTH

AF:

0.000490

ExAC

AF:

0.0000822

AC:

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 31, 2022

The c.101A>C (p.Q34P) alteration is located in exon 2 (coding exon 1) of the ATXN7 gene. This alteration results from a A to C substitution at nucleotide position 101, causing the glutamine (Q) at amino acid position 34 to be replaced by a proline (P). 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

0.073

BayesDel_addAF

Benign

-0.15

BayesDel_noAF

Benign

-0.45

Cadd

Benign

Dann

Benign

0.77

Eigen

Benign

-0.19

Eigen_PC

Benign

-0.22

FATHMM_MKL

Benign

0.63

LIST_S2

Benign

0.36

T;T;T;.;.

M_CAP

Benign

0.011

MetaRNN

Benign

0.080

T;T;T;T;T

MetaSVM

Benign

-1.1

MutationTaster

Benign

0.99

D;D;D;D

PrimateAI

Pathogenic

0.80

Polyphen

0.82, 0.89

.;P;P;P;P

Vest4

0.38, 0.39, 0.38

MutPred

0.21

Gain of glycosylation at Q34 (P = 0.0103);Gain of glycosylation at Q34 (P = 0.0103);Gain of glycosylation at Q34 (P = 0.0103);Gain of glycosylation at Q34 (P = 0.0103);Gain of glycosylation at Q34 (P = 0.0103);

MVP

0.65

ClinPred

0.12

GERP RS

2.9

Varity_R

0.18

gMVP

0.22

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