Is ABCD4 p.Phe222= (c.666T>C) pathogenic?

ABCD4 p.Phe222= (c.666T>C) is classified Likely benign in ABCD4 (ClinVar, Single submitter, 1 submitter; last evaluated 2025-12-08). Very rare (popmax 0.000339%, nfe); Associated with methylmalonic acidemia with homocystinuria, type cblJ.

What condition is associated with ABCD4 p.Phe222= (c.666T>C)?

ABCD4 p.Phe222= (c.666T>C) is associated with methylmalonic acidemia with homocystinuria, type cblJ (ClinVar).

How common is ABCD4 p.Phe222= (c.666T>C) in the general population?

ABCD4 p.Phe222= (c.666T>C) is very rare (popmax 0.000339%, nfe) (gnomAD).

How is Methylmalonic acidemia with homocystinuria inherited?

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

ABCD4 p.Phe222=

c.666T>C · VCV4765494

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.000339%, nfe)

Conditions

methylmalonic acidemia with homocystinuria, type cblJ

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
REVEL	0.065	moderately benign-leaning
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 1.6	GERP -3.2, phastCons 1
Overall
CADD	13.39	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000339% European (non-Finnish) · 4/1,179,848 alleles

Filtering AF 7.9e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 5.4e-05%

Overall 0.000274% 4/1,461,222 alleles · very rare

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: ABCD4
Protein: p.Phe222=
Coding: c.666T>C
MANE Select: NM_005050
Type: single nucleotide variant
Location: chr14:74295856 (GRCh38)
Gene constraint: LOEUF 0.772 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 87.18 · 4 PDB
Residue 222: the abc transmembrane type-1 domain

Full ABCD4 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

methylmalonic acidemia with homocystinuria, type cblJ — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Methylmalonic acidemia with homocystinuria (Orphanet):

Inheritance: Autosomal recessive, X-linked recessive
Onset: All ages

Similar variants

ABCD4 p.Phe222Leu Uncertain significance ★ ⚠ same residue
ABCD4 c.542+1G>T Pathogenic ★★ same condition
ABCD4 p.Arg432Gln Likely pathogenic ★★ same condition
ABCD4 p.Asn141Lys Pathogenic/Likely pathogenic ★★ same condition
ABCD4 p.Gln530Ter Pathogenic/Likely pathogenic ★★ same condition
ABCD4 p.Tyr176Ter Pathogenic/Likely pathogenic ★★ same condition
ABCD4 c.1028+5G>A Uncertain significance ★★ same condition
ABCD4 c.425+6C>T Uncertain significance ★★ 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/abcd4-p-phe222 (accessed [today's date]).

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