Is AFG2A c.446+18G>A pathogenic?

AFG2A c.446+18G>A is classified Likely benign in AFG2A (ClinVar, Single submitter, 1 submitter; last evaluated 2026-01-19). Very rare (popmax 0.00903%, nfe); Associated with microcephaly-intellectual disability-sensorineural hearing loss-epilepsy-abnormal muscle tone syndrome.

How common is AFG2A c.446+18G>A in the general population?

AFG2A c.446+18G>A is very rare (popmax 0.00903%, nfe) (gnomAD).

AFG2A c.446+18G>A

Q: What condition is associated with AFG2A c.446+18G>A?

AFG2A c.446+18G>A is associated with microcephaly-intellectual disability-sensorineural hearing loss-epilepsy-abnormal muscle tone syndrome (ClinVar).

rs372047960 · VCV1505091

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.00903%, nfe)

Conditions

microcephaly-intellectual disability-sensorineural hearing loss-epilepsy-abnormal muscle tone syndrome

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
Splice region	donor +18	near-intronic (+18 nt from the splice site)
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 1.3	GERP -0.63, phastCons 0.91
Non-coding constraint	Z 0.38	1 kb window · o/e 0.97 · regional · uncalibrated
Overall
CADD	15.8	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00903% European (non-Finnish) · 104/1,151,382 alleles

Filtering AF 0.00759% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.00709%

Overall 0.00723% 112/1,550,028 alleles · very rare

Ancestry group	Frequency	1 in
European (non-Finnish)grpmax	0.00903%	11,071
Remaining individualsnot grpmax-eligible	0.00836%	11,967
African / African-American	0.00278%	35,922
East Asian	0.00235%	42,502

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: AFG2A
Coding: c.446+18G>A
MANE Select: NM_145207
dbSNP: rs372047960
Type: single nucleotide variant
Location: chr4:122929215 (GRCh38)
Structure: AlphaFold pLDDT 73.21 · 2 PDB

Full AFG2A gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

microcephaly-intellectual disability-sensorineural hearing loss-epilepsy-abnormal muscle tone syndrome — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Similar variants

AFG2A c.1714+1G>A Pathogenic ★★ same condition
AFG2A c.446+1G>A Likely pathogenic ★★ same condition
AFG2A p.Ala844Val Pathogenic/Likely pathogenic ★★ ⚠ same condition
AFG2A p.Arg445Ter Pathogenic/Likely pathogenic ★★ same condition
AFG2A p.Arg510Ter Pathogenic/Likely pathogenic ★★ same condition
AFG2A p.Arg514Ter Pathogenic/Likely pathogenic ★★ same condition
AFG2A p.Arg538Ter Pathogenic/Likely pathogenic ★★ same condition
AFG2A p.Arg655Ter 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/afg2a-c-446-plus-18g-a (accessed [today's date]).

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