22-50625182-CGGG-CGGGG

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1_ModeratePM2PP5_Very_Strong

The NM_000487.6(ARSA):​c.1492_1493insC​(p.Arg498ProfsTer75) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000439 in 1,594,474 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely pathogenic (β˜…β˜…).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000042 ( 0 hom. )

Consequence

ARSA
NM_000487.6 frameshift

Scores

Not classified

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5

Conservation

PhyloP100: -0.608
Variant links:
Genes affected
ARSA (HGNC:713): (arylsulfatase A) The protein encoded by this gene hydrolyzes cerebroside sulfate to cerebroside and sulfate. Defects in this gene lead to metachromatic leucodystrophy (MLD), a progressive demyelination disease which results in a variety of neurological symptoms and ultimately death. Alternatively spliced transcript variants have been described for this gene. [provided by RefSeq, Dec 2010]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 12 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0248 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 22-50625182-C-CG is Pathogenic according to our data. Variant chr22-50625182-C-CG is described in ClinVar as [Likely_pathogenic]. Clinvar id is 371650.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
ARSANM_000487.6 linkuse as main transcriptc.1492_1493insC p.Arg498ProfsTer75 frameshift_variant 8/8 ENST00000216124.10 NP_000478.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
ARSAENST00000216124.10 linkuse as main transcriptc.1492_1493insC p.Arg498ProfsTer75 frameshift_variant 8/81 NM_000487.6 ENSP00000216124 P1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152216
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000460
AC:
1
AN:
217596
Hom.:
0
AF XY:
0.00000835
AC XY:
1
AN XY:
119784
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:
0.0000104
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000416
AC:
6
AN:
1442258
Hom.:
0
Cov.:
32
AF XY:
0.00000559
AC XY:
4
AN XY:
715878
show subpopulations
Gnomad4 AFR exome
AF:
0.0000301
Gnomad4 AMR exome
AF:
0.00
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:
0.00000453
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152216
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74376
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
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

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Metachromatic leukodystrophy Pathogenic:4
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJun 16, 2023For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this frameshift affects ARSA function (PMID: 19021637). Algorithms developed to predict the effect of variants on protein structure and function are not available or were not evaluated for this variant. ClinVar contains an entry for this variant (Variation ID: 371650). This variant is also known as g.2590_2591dupC. This frameshift has been observed in individual(s) with metachromatic leukodystrophy (PMID: 19021637, 26462614). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. 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 sequence change results in a frameshift in the ARSA gene (p.Arg498Profs*75). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 12 amino acid(s) of the ARSA protein and extend the protein by 62 additional amino acid residues. -
Likely pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpDec 20, 2018Variant summary: ARSA c.1492dupC (p.Arg498ProfsX75) causes a frameshift which results in an extension of the protein. The variant allele was found at a frequency of 4.7e-06 in 214108 control chromosomes. c.1492dupC has been reported in the literature in two related individuals affected with Metachromatic Leukodystrophy (Lugowska_2009). These data indicate that the variant may be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in 10% of normal activity (Lugowska_2009). One clinical diagnostic laboratory has submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation and classified the variant as likely pathogenic. Based on the evidence outlined above, the variant was classified as likely pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingCounsylNov 08, 2016- -
Pathogenic, criteria provided, single submitterclinical testingSuma Genomics, Suma Genomics-- -
not provided Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingGenetic Services Laboratory, University of ChicagoFeb 04, 2019DNA sequence analysis of the ARSA gene demonstrated a one base pair duplication in exon 8, c.1492dup. This duplication is predicted to result in an amino acid frameshift and creates a premature stop codon 74 amino acids downstream of the variant, p.Arg498Profs*75. This sequence change is predicted to result in an abnormal transcript, which may be degraded, or may lead to the production of a truncated ARSA protein with potentially abnormal function. While this duplication has not been previously described in the literature, other duplications and deletions in the exon 8 of the ARSA gene have been described in patients with ARSA-related disorders. The c.1492dup sequence change has been described in the gnomAD database with a low population frequency of 0.00047%(dbSNP rs774153480). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction

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: rs774153480; hg19: chr22-51063610; API