Genetic Variant NM_001377405.1:c.54G>C (chr3-63912652-G-C) – ACMG Classification: Likely_benign (-2 pts)

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2BP4_ModerateBP6BP7

The NM_001377405.1(ATXN7):c.54G>C(p.Ala18Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000135 in 147,674 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (no stars).

Frequency

Genomes: 𝑓 0.000014 ( 0 hom., cov: 32)

Consequence

ATXN7
NM_001377405.1 synonymous

Scores

Clinical Significance

Likely benign no assertion criteria provided B:1

Conservation

PhyloP100: -0.0940

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 -2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.37).

BP6

Variant 3-63912652-G-C is Benign according to our data. Variant chr3-63912652-G-C is described in ClinVar as [Likely_benign]. Clinvar id is 3046008.Status of the report is no_assertion_criteria_provided, 0 stars.

BP7

Synonymous conserved (PhyloP=-0.094 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ATXN7	NM_001377405.1 link	c.54G>C	p.Ala18Ala	synonymous_variant	Exon 3 of 13	ENST00000674280.1	NP_001364334.1
ATXN7	NM_001177387.1 link	c.54G>C	p.Ala18Ala	synonymous_variant	Exon 2 of 13		NP_001170858.1	O15265-2
ATXN7	NM_000333.4 link	c.54G>C	p.Ala18Ala	synonymous_variant	Exon 3 of 13		NP_000324.1	O15265-1Q9UPD8
ATXN7	NM_001377406.1 link	c.54G>C	p.Ala18Ala	synonymous_variant	Exon 2 of 12		NP_001364335.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ATXN7	ENST00000674280.1 link	c.54G>C	p.Ala18Ala	synonymous_variant	Exon 3 of 13		NM_001377405.1	ENSP00000501377.1		O15265-1

Frequencies

GnomAD3 genomes

AF:

0.0000136

AC:

AN:

147572

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000134

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD4 exome

Cov.:

GnomAD4 genome

AF:

0.0000135

AC:

AN:

147674

Hom.:

Cov.:

AF XY:

0.0000139

AC XY:

AN XY:

71938

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000134

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000302

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: no assertion criteria provided

LINK: link

Submissions by phenotype

ATXN7-related disorder

Benign:1

Apr 25, 2019

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.37

CADD

Benign

DANN

Benign

0.81

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

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