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PSAP p.Leu489=

c.1467G>A · VCV3712859

Likely benign Single submitter
Classification
Likely benign
ClinVar
Review
Single submitter ★☆☆☆
ClinVar · 1 submitter
gnomAD v4.1
Rare
very rare (popmax 0.000169%, nfe)
Conditions
1
metachromatic leukodystrophy due to saposin B deficiency

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI—not assessed · no allele here is in the release
Constraint at this position
ConservationphyloP -0.72GERP -3.1
Overall
CADD0.502PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes
Grpmax group 0.000169% European (non-Finnish) · 2/1,180,038 alleles
Filtering AF 2.8e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 1.1e-05%
Overall 0.000124% 2/1,614,168 alleles · very rare exomes 2/1,461,874 · genomes 0/152,294 · joint denominator

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene
PSAP
Protein
p.Leu489=
Coding
c.1467G>A
MANE Select
NM_002778
Type
single nucleotide variant
Location
chr10:71818689 (GRCh38)
Gene constraint
LOEUF 0.507 · pLI 0.95 (gnomAD)
Structure
AlphaFold pLDDT 73.90 · 21 PDB
Residue 489
the saposin a-type 2 domain
Full PSAP gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

metachromatic leukodystrophy due to saposin B deficiency — 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

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/psap-p-leu489 (accessed [today's date]).

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