rs774323189

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_000049.4(ASPA):​c.859G>A​(p.Ala287Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000929 in 1,614,016 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 Likely pathogenic (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

ASPA
NM_000049.4 missense

Scores

10
6
3

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 7.74
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 14 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.992
PP5
Variant 17-3499005-G-A is Pathogenic according to our data. Variant chr17-3499005-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 188803.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-3499005-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ASPANM_000049.4 linkc.859G>A p.Ala287Thr missense_variant Exon 6 of 6 ENST00000263080.3 NP_000040.1 P45381Q6FH48

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ASPAENST00000263080.3 linkc.859G>A p.Ala287Thr missense_variant Exon 6 of 6 1 NM_000049.4 ENSP00000263080.2 P45381
ASPAENST00000456349.6 linkc.859G>A p.Ala287Thr missense_variant Exon 7 of 7 1 ENSP00000409976.2 P45381
SPATA22ENST00000541913.5 linkc.-74+14407C>T intron_variant Intron 1 of 8 2 ENSP00000441920.1 F5GWB9
SPATA22ENST00000570318.1 linkc.-74+14606C>T intron_variant Intron 1 of 1 2 ENSP00000459147.1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152180
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251342
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135848
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:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000821
AC:
12
AN:
1461836
Hom.:
0
Cov.:
31
AF XY:
0.00000825
AC XY:
6
AN XY:
727210
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.0000224
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:
0.00000809
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000197
AC:
3
AN:
152180
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74338
show subpopulations
Gnomad4 AFR
AF:
0.0000483
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000207
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000113
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Spongy degeneration of central nervous system Pathogenic:6
Mar 17, 2017
Natera, Inc.
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 05, 2024
Baylor Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

May 24, 2014
Counsyl
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: literature only

- -

Apr 02, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Feb 05, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 287 of the ASPA protein (p.Ala287Thr). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individual(s) with Canavan disease (PMID: 12638939, 16854607, 26992473). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 188803). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt ASPA protein function with a positive predictive value of 95%. For these reasons, this variant has been classified as Pathogenic. -

Nov 07, 2021
Genome-Nilou Lab
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Pathogenic:1
Jun 01, 2022
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Canavan Disease, Familial Form Pathogenic:1
Aug 04, 2016
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: The ASPA c.859G>A (p.Ala287Thr) variant involves the alteration of a conserved nucleotide. 4/4 in silico tools predict a damaging outcome for this variant (SNPs&GO not captured due to low reliability index). The C-domain of the protein forms a pocket that accommodates the acetyl group of NAA and puts severe restriction on the size of this portion of substrate. The tight pocket is formed by residues Thr-118, Gln-184, Phe-282, Glu-285, Ala-287, and Tyr-288. Thus, p.Ala287Thr is predicted to alter the hydrogen bonding network, which may lead to destabilization of interaction between the N- and C-domain (PMID: 17194761). This variant was found in 3/120632 control chromosomes at a frequency of 0.0000249, which does not exceed the estimated maximal expected allele frequency of a pathogenic ASPA variant (0.0079057). ASPA c.859G>A has been reported in numerous patients with Canavan disease. In addition, one clinical diagnostic laboratory classified this variant as likely pathogenic. Taken together, this variant is classified as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.77
BayesDel_addAF
Pathogenic
0.54
D
BayesDel_noAF
Pathogenic
0.53
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.99
D;D
Eigen
Uncertain
0.33
Eigen_PC
Benign
0.18
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Benign
0.78
.;T
M_CAP
Pathogenic
0.30
D
MetaRNN
Pathogenic
0.99
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.4
M;M
PrimateAI
Uncertain
0.59
T
PROVEAN
Uncertain
-3.5
D;D
REVEL
Pathogenic
0.89
Sift
Uncertain
0.0020
D;D
Sift4G
Uncertain
0.0050
D;D
Polyphen
1.0
D;D
Vest4
0.93
MutPred
0.92
Gain of glycosylation at A287 (P = 0.1084);Gain of glycosylation at A287 (P = 0.1084);
MVP
0.98
MPC
0.27
ClinPred
0.97
D
GERP RS
3.7
Varity_R
0.76
gMVP
0.90

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.

Other links and lift over

dbSNP: rs774323189; hg19: chr17-3402299; COSMIC: COSV53980884; API