Is ASPM p.Arg243Ter (c.727C>T) pathogenic?

ASPM p.Arg243Ter (c.727C>T) is classified Pathogenic in ASPM (ClinVar, Multiple submitters, 3 submitters; last evaluated 2026-01-12). Very rare (popmax 0.00266%, afr); Associated with microcephaly.

What condition is associated with ASPM p.Arg243Ter (c.727C>T)?

ASPM p.Arg243Ter (c.727C>T) is associated with microcephaly (ClinVar).

How common is ASPM p.Arg243Ter (c.727C>T) in the general population?

ASPM p.Arg243Ter (c.727C>T) is very rare (popmax 0.00266%, afr) (gnomAD).

ASPM p.Arg243Ter

c.727C>T · rs1463609963 · VCV1172591

Pathogenic Multiple submitters

Classification

Pathogenic

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Rare

very rare (popmax 0.00266%, afr)

Conditions

microcephaly

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function
NMD	predicted	premature termination codon in exon 3 of 28
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 3.2	GERP 1.7, phastCons 0.36
Overall
CADD	29.7	PHRED · no single calibrated threshold — expert panels disagree

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

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.00266% African / African-American · 2/75,048 alleles

Filtering AF 0.000442% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.000166%

Overall 0.000342% 5/1,461,588 alleles · very rare

Ancestry group	Frequency	1 in
African / African-Americangrpmax	0.00266%	37,524
European (non-Finnish)	0.000254%	393,295

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: ASPM
Protein: p.Arg243Ter
Coding: c.727C>T
MANE Select: NM_018136
dbSNP: rs1463609963
Type: single nucleotide variant
Location: chr1:197143525 (GRCh38)
Gene constraint: LOEUF 0.766 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)

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

Disease context

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

Similar variants

ASPM c.9084+5G>A Likely pathogenic ★★ same condition
ASPM p.Glu1266Ter Pathogenic ★★ same condition
ASPM p.Leu3109fs Pathogenic/Likely pathogenic ★★ same condition
ASPM p.Ser577fs Pathogenic/Likely pathogenic ★★ same condition
ASPM p.Glu2525fs Likely pathogenic ★ same condition
ASPM c.2419+2T>C Pathogenic/Likely pathogenic ★★ same type
ASPM c.2488-1G>C Pathogenic/Likely pathogenic ★★ same type
ASPM c.2936+5G>A Likely pathogenic ★★ same type

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/aspm-p-arg243ter (accessed [today's date]).

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