chr17-3481603-C-CA

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000049.4(ASPA):​c.244dupA​(p.Met82AsnfsTer8) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000682 in 1,612,574 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000062 ( 0 hom. )

Consequence

ASPA
NM_000049.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:9

Conservation

PhyloP100: 1.75

Publications

1 publications found
Variant links:
Genes affected
ASPA (HGNC:756): (aspartoacylase) This gene encodes an enzyme that catalyzes the conversion of N-acetyl_L-aspartic acid (NAA) to aspartate and acetate. NAA is abundant in the brain where hydrolysis by aspartoacylase is thought to help maintain white matter. This protein is an NAA scavenger in other tissues. Mutations in this gene cause Canavan disease. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jul 2008]
SPATA22 (HGNC:30705): (spermatogenesis associated 22) Predicted to be involved in regulation of meiotic cell cycle. Predicted to act upstream of or within several processes, including fertilization; gamete generation; and meiosis I cell cycle process. Predicted to be located in chromosome. [provided by Alliance of Genome Resources, Apr 2022]
SPATA22 Gene-Disease associations (from GenCC):
  • infertility disorder
    Inheritance: AR Classification: MODERATE Submitted by: Ambry Genetics

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ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 17-3481603-C-CA is Pathogenic according to our data. Variant chr17-3481603-C-CA is described in ClinVar as Pathogenic. ClinVar VariationId is 370554.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ASPANM_000049.4 linkc.244dupA p.Met82AsnfsTer8 frameshift_variant Exon 2 of 6 ENST00000263080.3 NP_000040.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ASPAENST00000263080.3 linkc.244dupA p.Met82AsnfsTer8 frameshift_variant Exon 2 of 6 1 NM_000049.4 ENSP00000263080.2

Frequencies

GnomAD3 genomes
AF:
0.0000132
AC:
2
AN:
151828
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000242
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
GnomAD2 exomes
AF:
0.00000400
AC:
1
AN:
249854
AF XY:
0.00000741
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000887
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000616
AC:
9
AN:
1460746
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
726644
show subpopulations
African (AFR)
AF:
0.0000598
AC:
2
AN:
33458
American (AMR)
AF:
0.00
AC:
0
AN:
44674
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26106
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39610
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86092
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53370
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5586
European-Non Finnish (NFE)
AF:
0.00000540
AC:
6
AN:
1111508
Other (OTH)
AF:
0.00
AC:
0
AN:
60342
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000132
AC:
2
AN:
151828
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74120
show subpopulations
African (AFR)
AF:
0.0000242
AC:
1
AN:
41344
American (AMR)
AF:
0.00
AC:
0
AN:
15218
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4814
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10510
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67966
Other (OTH)
AF:
0.00
AC:
0
AN:
2084
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:9
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Spongy degeneration of central nervous system Pathogenic:6
Nov 07, 2021
Genome-Nilou Lab
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 26, 2016
Counsyl
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Mar 20, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 18, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Met82Asnfs*8) in the ASPA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in ASPA are known to be pathogenic (PMID: 12638939). This variant is present in population databases (rs756198538, gnomAD 0.002%). This premature translational stop signal has been observed in individual(s) with clinical features of Canavan disease (PMID: 10407784, 10909858, 12638939). This variant is also known as 245insA or 244–245insA. ClinVar contains an entry for this variant (Variation ID: 370554). For these reasons, this variant has been classified as Pathogenic. -

May 03, 2020
Genomic Research Center, Shahid Beheshti University of Medical Sciences
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 17, 2017
Natera, Inc.
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Inborn genetic diseases Pathogenic:1
Sep 01, 2015
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.244dupA pathogenic mutation, located in coding exon 2 of the ASPA gene, results from a duplication of A at nucleotide position 244, causing a translational frameshift with a predicted alternate stop codon. This mutation is also called c.245insA in the literature. In one study, this mutation was detected in the homozygous state in a Norwegian individual diagnosed with Canavan disease at 4.5 months (Olsen TR, et al. J. Med. Genet. 2002;39(9):e55). This mutation has also been detected in four alleles from unrelated non-Ashkenazi Jewish individuals with Canavan disease (Elpeleg ON, et al. J. Inherit. Metab. Dis. 1999;22(4):531-4; Zeng BJ, et al. Mol. Genet. Metab;89(1-2):156-63). In addition to the clinical data presented in the literature, since frameshifts are typically deleterious in nature, this alteration is interpreted as a disease-causing mutation (ACMG Recommendations for Standards for Interpretation and Reporting of Sequence Variations. Revision 2007. Genet Med. 2008;10:294). -

not provided Pathogenic:1
Mar 22, 2022
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 10407784, 12205125) -

Canavan Disease, Familial Form Pathogenic:1
May 29, 2018
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: ASPA c.244dupA (p.Met82AsnfsX8) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory (eg. c.631G>T, p.Glu211X; c.693C>A, p.Tyr231X). The variant allele was found at a frequency of 7.3e-06 in 275364 control chromosomes. This frequency is lower than expected for a pathogenic variant in ASPA causing Canavan Disease (7.3e-06 vs 0.0079), allowing no conclusion about variant significance. The c.244dupA has been reported in the literature in individuals affected with a confirmed diagnosis of Canavan Disease, by the demonstration of increased levels of NAA in urine as well as aspartoacylase deficiency detected in skin fibroblasts. These data indicate that the variant is likely to be associated with disease. To our knowledge, no direct experimental evidence demonstrating an impact on protein function has been reported, although it is expected to result in a complete lack of activity (Elpeleg_1999). Other frameshifts in this region (c.244delA and c.244_245delAT) have been reported in pts with Canavan Disease with complete lack of enzymatic activity ((Zeng_2002). One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as pathogenic/likely pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
1.8
Mutation Taster
=0/200
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs756198538; hg19: chr17-3384897; COSMIC: COSV53981311; API