Is ARSA p.Phe377fs (c.1128_1129dup) pathogenic?

ARSA p.Phe377fs (c.11281129dup) is classified Pathogenic in ARSA (ClinVar, Single submitter, 1 submitter; last evaluated 2022-08-08). Absent from gnomAD; Associated with metachromatic leukodystrophy.

What condition is associated with ARSA p.Phe377fs (c.1128_1129dup)?

ARSA p.Phe377fs (c.1128_1129dup) is associated with metachromatic leukodystrophy (ClinVar).

How common is ARSA p.Phe377fs (c.1128_1129dup) in the general population?

ARSA p.Phe377fs (c.1128_1129dup) is absent from gnomAD (gnomAD).

How is Metachromatic leukodystrophy inherited?

Typically Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

ARSA p.Phe377fs

c.1128_1129dup · rs2518324057 · VCV2022754

Pathogenic Single submitter

Classification

Pathogenic

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

Consequence

frameshift

predicted LoF

gnomAD v4.1

Not reported

no gnomAD frequency available for this variant

Conditions

metachromatic leukodystrophy

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	frameshift	predicted loss-of-function
NMD	predicted	premature termination codon in exon 7 of 8
Splicing
SpliceAI	—	not assessed · substitutions only
Constraint at this position
Conservation	phyloP 9	GERP 2.2, phastCons 1

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

dbSNP / gnomAD

No gnomAD frequency available for this variant. This is missing data, not an absence: the variant may or may not be present in gnomAD. Rarity (ACMG PM2) and BA1/BS1 cannot be assessed for it.

Variant & gene context

Gene: ARSA
Protein: p.Phe377fs
Coding: c.1128_1129dup
MANE Select: NM_000487
dbSNP: rs2518324057
Type: Duplication
Location: chr22:50625659 (GRCh38)
Gene constraint: LOEUF 1.166 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 96.43 · 10 PDB
Residue 377: a UniProt-annotated variant site (in mld; severe); a disulfide bond

Full ARSA gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

metachromatic leukodystrophy — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Metachromatic leukodystrophy (Orphanet):

Inheritance: Autosomal recessive
Onset: Adolescent, Adult, Childhood, Infancy
Prevalence: 1-9 / 100 000 (Europe)

Similar variants

ARSA p.Phe377del Likely pathogenic ★★ same residue
ARSA p.Arg498fs Pathogenic/Likely pathogenic ★★ same condition
ARSA p.Arg99fs Pathogenic ★★ same condition
ARSA p.Gly449fs Pathogenic ★★ same condition
ARSA p.Gly81fs Pathogenic/Likely pathogenic ★★ same condition
ARSA p.His140fs Pathogenic ★★ same condition
ARSA p.Leu183fs Pathogenic ★★ same condition
ARSA p.Leu429fs Pathogenic/Likely pathogenic ★★ same condition

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/arsa-p-phe377fs (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown