NM_000435.2:c.3257A>C (p.Asp1086Ala) is a missense variant in NOTCH3 exon 20. This variant is absent from large population databases (gnomAD v2.1, v4.1, and gnomAD-Canada; PM2_supporting). No pathogenic or benign criteria beyond PM2_supporting are met. The variant is not cysteine-altering and lies outside known mutational hotspots. No functional, segregation, de novo, case-control, or clinical classification data are available. Based on ACMG/AMP 2015 generic classification rules (PMID:25741868), a single supporting pathogenic criterion (PM2_supporting) is insufficient to reach Likely Pathogenic or any other classification tier. This variant is classified as a Variant of Uncertain Significance (VUS).¹