rs199476366

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM1PM2PM5PP2PP3_StrongPP5

The NM_000487.6(ARSA):​c.737G>T​(p.Arg246Leu) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,772 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R246H) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

ARSA
NM_000487.6 missense

Scores

8
7
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:1

Conservation

PhyloP100: 5.93

Publications

0 publications found
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]
ARSA Gene-Disease associations (from GenCC):
  • metachromatic leukodystrophy
    Inheritance: AR Classification: DEFINITIVE Submitted by: Myriad Women’s Health, ClinGen
  • metachromatic leukodystrophy, juvenile form
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 12 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000487.6
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr22-50626708-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 68148.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 159 curated pathogenic missense variants (we use a threshold of 10). The gene has 11 curated benign missense variants. Gene score misZ: 0.38013 (below the threshold of 3.09). Trascript score misZ: -0.56919 (below the threshold of 3.09). GenCC associations: The gene is linked to metachromatic leukodystrophy, juvenile form, metachromatic leukodystrophy.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.953
PP5
Variant 22-50626708-C-A is Pathogenic according to our data. Variant chr22-50626708-C-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2581426.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
ARSANM_000487.6 linkc.737G>T p.Arg246Leu missense_variant Exon 4 of 8 ENST00000216124.10 NP_000478.3 P15289A0A0C4DFZ2B4DVI5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
ARSAENST00000216124.10 linkc.737G>T p.Arg246Leu missense_variant Exon 4 of 8 1 NM_000487.6 ENSP00000216124.5 A0A0C4DFZ2

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461772
Hom.:
0
Cov.:
33
AF XY:
0.00000138
AC XY:
1
AN XY:
727180
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53324
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111992
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:1Uncertain:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Metachromatic leukodystrophy Pathogenic:1
Oct 22, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 246 of the ARSA protein (p.Arg246Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with ARSA-related conditions. 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 ARSA protein function with a positive predictive value of 95%. This variant disrupts the p.Arg246 amino acid residue in ARSA. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 9090526, 22993277, 25965562, 26462614). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

not specified Uncertain:1
Aug 29, 2023
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: ARSA c.737G>T (p.Arg246Leu) results in a non-conservative amino acid change located in the Sulfatase, N-terminal (IPR000917) of the encoded protein sequence. This alters a highly conserved residue (HGMD) in which two other missense variants (p.Arg246Cys, p.Arg246His) have been classified as pathogenic/likely pathogenic by ClinVar submitters citing published clinical evidence. Four of four in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 251028 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.737G>T in individuals affected with Metachromatic Leukodystrophy and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.48
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Benign
0.39
T;T;T;.;T
Eigen
Uncertain
0.59
Eigen_PC
Uncertain
0.56
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.93
.;.;.;D;D
M_CAP
Pathogenic
0.80
D
MetaRNN
Pathogenic
0.95
D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
PhyloP100
5.9
PrimateAI
Uncertain
0.68
T
PROVEAN
Pathogenic
-5.7
D;D;D;D;D
REVEL
Pathogenic
0.92
Sift
Uncertain
0.0050
D;D;D;D;D
Sift4G
Uncertain
0.010
D;D;D;D;D
Vest4
0.87
MVP
0.81
ClinPred
1.0
D
GERP RS
5.4
gMVP
0.95
Mutation Taster
=5/95
disease causing

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

Other links and lift over

dbSNP: rs199476366; hg19: chr22-51065136; API