The FLT3 c.1732_1797dup (p.Met578_Tyr599dup) variant has not been observed in somatic cancers in COSMIC and has not been reported in ClinVar.¹ This variant is absent from gnomAD v2.1 and gnomAD v4.1, with an observed population frequency of 0, which is below the default PM2 rarity threshold of 0.1%.² The duplicated segment spans the FLT3 juxtamembrane ITD hotspot and includes the classic codon 589-599 activating cluster, which supports hotspot-class evidence, but no exact-variant OncoKB functional assertion was identified for p.Met578_Tyr599dup.³ SpliceAI predicts no significant splice impact for this variant, with a maximum delta score of 0.18.⁴