rs74315471

chr22-50626706-C-T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1 PM2 PP3_Strong PP5_Very_Strong

The NM_000487.6(ARSA):c.739G>A(p.Gly247Arg) variant causes a missense change. The variant allele was found at a frequency of 0.0000235 in 1,614,008 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 (★★). Synonymous variant affecting the same amino acid position (i.e. G247G) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000025 (0 hom.)
• Consequence: ARSA NM_000487.6 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:10 O:1
• Conservation: PhyloP100: 5.79

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 16 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, 4 uncertain in NM_000487.6
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.942
• PP5: Variant 22-50626706-C-T is Pathogenic according to our data. Variant chr22-50626706-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 3074.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr22-50626706-C-T is described in Lovd as [Pathogenic]. Variant chr22-50626706-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ARSA	NM_000487.6	c.739G>A	p.Gly247Arg	missense_variant	4/8	ENST00000216124.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ARSA	ENST00000216124.10	c.739G>A	p.Gly247Arg	missense_variant	4/8	1	NM_000487.6	P1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152232 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000120 AC: 3 AN: 251038 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135786

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000882

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000246 AC: 36 AN: 1461776 Hom.: 0 Cov.: 33 AF XY: 0.0000275 AC XY: 20 AN XY: 727186

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000464

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000270

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152232 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74376

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000414

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:10 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Metachromatic leukodystrophy Pathogenic:7 Other:1

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 01, 2023	For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects ARSA function (PMID: 8101083). 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: 3074). This variant is also known as p.Gly245Arg. This missense change has been observed in individual(s) with metachromatic leukodystrophy (PMID: 8101083, 26553228, 31186049). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is present in population databases (rs74315471, gnomAD 0.003%). This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 247 of the ARSA protein (p.Gly247Arg). -
Pathogenic, criteria provided, single submitter	clinical testing	Foundation for Research in Genetics and Endocrinology, FRIGE's Institute of Human Genetics	Mar 23, 2024	A heterozygous missense variant in exon 4 of the ARSA gene that results in the amino acid substitution of Arginine for Glycine at codon 247 was detected. The observed variant c.739G>A has not been reported in the 1000 genomes and has a MAF of 0.0012% in the gnomAD database. The in silico prediction of the variant is damaging by MutationTaster2, SIFT, PolyPhen2. The reference codon is conserved across species. In summary, the variant meets our criteria to be classified as pathogenic. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Counsyl	May 01, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	Neuberg Centre For Genomic Medicine, NCGM	-	The missense c.739G>A (p.Gly247Arg) variant has been observed in individual(s) with metachromatic leukodystrophy (Liaw HR et al). Experimental studies have shown that this missense change affects ARSA function (Hasegawa Y et al). 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) indicates that this missense variant is expected to disrupt ARSA protein function. This variant is reported with the allele frequency (0.0012%) in the gnomad and novel in 1000 genome database. It has been submitted to ClinVar as Pathogenic. The amino acid Gly at position 247 is changed to a Arg changing protein sequence and it might alter its composition and physico-chemical properties. For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Victorian Clinical Genetics Services, Murdoch Childrens Research Institute	Jun 24, 2022	Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with metachromatic leukodystrophy (MIM#250100). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from glycine to arginine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD <0.01 for a recessive condition (v2: 3 heterozygotes, 0 homozygotes). (SP) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (I) 0704 - Another missense variant comparable to the one identified in this case has limited previous evidence for pathogenicity. p.(Gly247Glu) has been reported in a compound heterozygote individual with metachromatic leukodystrophy (PMID: 27779215). (SP) 0801 - This variant has strong previous evidence of pathogenicity in unrelated individuals. It has been reported in at least six homozygote or compound heterozygote individuals with metachromatic leukodystrophy; and consistently classified as pathogenic by diagnostic laboratories in ClinVar (PMIDs: 31186049, 21167507). This variant is also known as p.(Gly245Arg) in older manuscripts. (SP) 1205 - This variant has been shown to be maternally inherited (by trio analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München	Sep 08, 2017	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Suma Genomics	-	- -
not provided, no classification provided	literature only	GeneReviews	-	- -

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	May 29, 2014	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Aug 10, 2023	Published functional studies demonstrate G247R does not induce enzyme activity (Hasegawa et al., 1993); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Not observed at significant frequency in large population cohorts (gnomAD); Also known as p.(G245R) due to use of alternate nomenclature; This variant is associated with the following publications: (PMID: 26553228, 8101083, 21167507, 31186049, 36789546) -

Metachromatic leukodystrophy, severe Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Jul 01, 1993

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.46
Cadd	Pathogenic	30
Dann	Pathogenic	1.0
DEOGEN2	Benign	0.39	T;T;T;.;T
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.54
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.51	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D
MetaSVM	Pathogenic	0.93	D
MutationTaster	Benign	1.0	A;A;A;A;A;A;A
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-7.8	D;D;D;D;D
REVEL	Pathogenic	0.86
Sift	Pathogenic	0.0	D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;T;D
Vest4		0.95
MVP		0.95
ClinPred		1.0	D
GERP RS		5.4
gMVP		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs74315471; hg19: chr22-51065134;