rs199476392

Variant names:

• chr22-50625386-A-G
• rs199476392
• NM_000487.6:c.1289T>C

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Very_Strong

The NM_000487.6(ARSA):​c.1289T>C​(p.Leu430Pro) variant causes a missense change. The variant allele was found at a frequency of 0.00000138 in 1,449,994 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. L430F) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: ARSA NM_000487.6 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:1 O:1
• Conservation: PhyloP100: 6.85
• Publications: 2 publications found

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

ACMG classification

Our verdict: Pathogenic. The variant received 19 ACMG points.

• PM1: In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 17 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 chr22-50625387-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2860762.Status of the report is criteria_provided_single_submitter, 1 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, 0.983
• PP5: Variant 22-50625386-A-G is Pathogenic according to our data. Variant chr22-50625386-A-G is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 68119.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
ARSA	NM_000487.6	c.1289T>C	p.Leu430Pro	missense_variant	Exon 8 of 8	ENST00000216124.10	NP_000478.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ARSA	ENST00000216124.10	c.1289T>C	p.Leu430Pro	missense_variant	Exon 8 of 8	1	NM_000487.6	ENSP00000216124.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1449994 Hom.: 0 Cov.: 32 AF XY: 0.00000139 AC XY: 1 AN XY: 719530

African (AFR) AF: 0.0000301 AC: 1 AN: 33252

American (AMR) AF: 0.00 AC: 0 AN: 44220

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25562

East Asian (EAS) AF: 0.00 AC: 0 AN: 39460

South Asian (SAS) AF: 0.00 AC: 0 AN: 85568

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52164

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5728

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1104246

Other (OTH) AF: 0.0000167 AC: 1 AN: 59794

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3 Uncertain:1 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Metachromatic leukodystrophy Pathogenic:2 Uncertain:1

Aug 25, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is also known as p.L428P. For these reasons, this variant has been classified as Pathogenic. 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. ClinVar contains an entry for this variant (Variation ID: 68119). This missense change has been observed in individual(s) with clinical features of metachromatic leukodystrophy (PMID: 9272717, 26462614; Invitae). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces leucine, which is neutral and non-polar, with proline, which is neutral and non-polar, at codon 430 of the ARSA protein (p.Leu430Pro). -

Aug 11, 2021

Revvity Omics, Revvity

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Oct 18, 2024

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: ARSA c.1289T>C (p.Leu430Pro; also described as c.1283T>C, p.L428P in the literature) results in a non-conservative amino acid change in the encoded protein sequence. Four of four in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 244162 control chromosomes (gnomAD). c.1289T>C has been reported in the literature in individuals (both homozygous and compound heterozygotes) affected with metachromatic leukodystrophy (examples: Regis_1997, Cesani_2015, Grossi_2008, Internal data). These data indicate that the variant is likely to be associated with disease. The following publications have been ascertained in the context of this evaluation (PMID: 9272717, 26462614, 18693274). ClinVar contains an entry for this variant (Variation ID: 68119). Based on the evidence outlined above, the variant was classified as pathogenic. -

not provided Pathogenic:1 Other:1

Dec 01, 2022

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Reported previously in a patient with juvenile metachromatic leukodystrophy who harbored a second variant in the ARSA gene; phase unknown (Cesani et al., 2015); Not observed in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Also known as p.L428P; This variant is associated with the following publications: (PMID: 26462614, 18693274, 26659599, 27915290, 9272717) -

-

UniProtKB/Swiss-Prot

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.57
CADD	Uncertain	25
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.65	D;D;D;.;D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Benign	0.86	.;.;.;D;D
M_CAP	Pathogenic	0.62	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
PhyloP100		6.8
PrimateAI	Uncertain	0.68	T
PROVEAN	Pathogenic	-6.7	D;D;D;D;D
REVEL	Pathogenic	0.99
Sift	Uncertain	0.0010	D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D
Vest4		0.97
MVP		0.97
ClinPred		1.0	D
GERP RS		5.6
gMVP		0.97
Mutation Taster		=0/100	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

Other links and lift over

dbSNP: rs199476392; hg19: chr22-51063814;