rs74315461

chr22-50627261-C-Achr22-50627261-C-Gchr22-50627261-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Moderate

The NM_000487.6(ARSA):c.370G>T(p.Gly124Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000207 in 1,449,390 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. G124S) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: ARSA NM_000487.6 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 4.89

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]

ACMG classification

Verdict is Pathogenic. Variant got 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, 7 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 chr22-50627260-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 800496.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.958
• PP5: Variant 22-50627261-C-A is Pathogenic according to our data. Variant chr22-50627261-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1511352.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr22-50627261-C-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ARSA	NM_000487.6	c.370G>T	p.Gly124Cys	missense_variant	2/8	ENST00000216124.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ARSA	ENST00000216124.10	c.370G>T	p.Gly124Cys	missense_variant	2/8	1	NM_000487.6	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000207 AC: 3 AN: 1449390 Hom.: 0 Cov.: 33 AF XY: 0.00000139 AC XY: 1 AN XY: 720304

Gnomad4 AFR exome AF: 0.00

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: 0.00000271

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Metachromatic leukodystrophy Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Invitae

May 27, 2023

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. This variant disrupts the p.Gly124 amino acid residue in ARSA. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 32632536, 33185815). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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: 1511352). This variant is also known as p.G122C. This missense change has been observed in individual(s) with metachromatic leukodystrophy (PMID: 19021637). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with cysteine, which is neutral and slightly polar, at codon 124 of the ARSA protein (p.Gly124Cys). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
Cadd	Pathogenic	27
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.63	D;D;D;.;D
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.97	D
M_CAP	Pathogenic	0.32	D
MetaRNN	Pathogenic	0.96	D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D;D;D;D;D
PrimateAI	Uncertain	0.73	T
PROVEAN	Pathogenic	-8.0	D;D;D;D;D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D
Vest4		0.88
MVP		0.98
ClinPred		1.0	D
GERP RS		3.7
gMVP		0.99

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

Other links and lift over

dbSNP: rs74315461; hg19: chr22-51065689;