NM_003000.3:c.172A>G (p.Met58Val) is a missense variant in SDHB, a tumor suppressor gene associated with autosomal dominant hereditary pheochromocytoma-paraganglioma.¹ This variant is absent from gnomAD v2.1 and v4.1, supporting PM2 at supporting level per generic ACMG/AMP 2015 criteria.² Six clinical laboratories have submitted this variant to ClinVar, all classifying it as Uncertain Significance (ClinVar variation ID: 459138).³ In silico predictions are indeterminate: SpliceAI predicts no splice impact (max delta 0.00) and BayesDel score is 0.338, which does not reach a pathogenic or benign threshold. REVEL score is unavailable.⁴ No functional studies, case reports, segregation data, or de novo observations have been identified for this variant in the reviewed literature or curated databases.⁵ No pathogenic missense variant at the same amino acid residue (Met58) was identified for PM5 comparison.⁶ The ClinGen Endocrine Tumor Predisposition Expert Panel specifications for SDHB (version 1.0.0) were identified but contained no parsed criterion-level rules; classification adheres to generic ACMG/AMP 2015 framework.⁷ With only PM2_Supporting met and no additional pathogenic or benign criteria satisfied, the variant remains a Variant of Uncertain Significance per ACMG/AMP 2015 combination rules (PMID:25741868).⁸