PS1
Not met: no pathogenic variant producing p.Thr138Asn is documented in ClinVar, the literature, or OncoKB — the only same-amino-acid report is a single somatic COSMIC occurrence.
PS2
Not assessed: no proband phenotype, parental testing, or trio data were available, so a confirmed de novo occurrence could not be evaluated.
PS3
Not assessed: no variant-specific functional studies exist; OncoKB lists this variant as 'Unknown Oncogenic Effect' with no reviewed functional evidence.
PS4
Not assessed: no case-control or cohort data exist; the only observation is a single somatic COSMIC occurrence, which cannot support PS4.
PM1
Not met: T138 is not a documented mutational hotspot — CancerHotspots lists no significant hotspot at this residue — and the established IDH2 hotspots are R140 and R172.
PM3
Not assessed: no second allele, phase, or segregation data exist — the variant is absent from ClinVar and gnomAD — so trans/cis status is unevaluable.
PM5
Not met: no different missense change at residue 138 is documented as pathogenic.
PM6
Not assessed: no parental or family genotype data exist, so an assumed de novo origin could not be evaluated.
PP1
Not assessed: no family segregation data are available — no affected relatives genotyped and no external segregation reports.
PP2
Not assessed: IDH2's rate of benign missense variation could not be established from any consulted source.
PP3
Not met: REVEL 0.736 is below the >=0.932 PP3 threshold, and SpliceAI max delta 0.00 predicts no splice impact.
PP4
Not assessed: no proband phenotype or family history was provided, so phenotype specificity could not be evaluated.
