rs774323189
Variant summary
Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A287S) has been classified as Uncertain significance.
Frequency
Consequence
NM_000049.4 missense
Scores
Clinical Significance
Conservation
Publications
- infertility disorderInheritance: AR Classification: MODERATE Submitted by: Ambry Genetics
Genome browser will be placed here
ACMG classification
Our verdict: Pathogenic. The variant received 19 ACMG points.
Transcripts
RefSeq
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| ASPA | ENST00000263080.3 | c.859G>A | p.Ala287Thr | missense_variant | Exon 6 of 6 | 1 | NM_000049.4 | ENSP00000263080.2 | ||
| ASPA | ENST00000456349.6 | c.859G>A | p.Ala287Thr | missense_variant | Exon 7 of 7 | 1 | ENSP00000409976.2 | |||
| SPATA22 | ENST00000541913.5 | c.-74+14407C>T | intron_variant | Intron 1 of 8 | 2 | ENSP00000441920.1 | ||||
| SPATA22 | ENST00000570318.1 | c.-74+14606C>T | intron_variant | Intron 1 of 1 | 2 | ENSP00000459147.1 |
Frequencies
GnomAD3 genomes AF: 0.0000197 AC: 3AN: 152180Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.00000398 AC: 1AN: 251342 AF XY: 0.00000736 show subpopulations
GnomAD4 exome AF: 0.00000821 AC: 12AN: 1461836Hom.: 0 Cov.: 31 AF XY: 0.00000825 AC XY: 6AN XY: 727210 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000197 AC: 3AN: 152180Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2AN XY: 74338 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
Spongy degeneration of central nervous system Pathogenic:6
- -
- -
This submission and the accompanying classification are no longer maintained by the submitter.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. -
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. -
- -
- -
not provided Pathogenic:1
- -
Canavan Disease, Familial Form Pathogenic:1
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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at