The NM_177438.2:c.5461A>G variant in DICER1 is a missense variant predicted to cause substitution of methionine by valine at amino acid 1821 (p.Met1821Val). This variant has an allele frequency of 0.000004 (1/236,934 alleles) across gnomAD v2.1.1 (non-cancer) with no more than one allele in any subpopulation, which is lower than the ClinGen DICER1 VCEP threshold (<0.000005) for PM2_Supporting, and therefore meets this criterion (PM2_Supporting). The computational predictor REVEL gives a score of 0.54, which is neither above nor below the thresholds predicting a damaging or benign impact on DICER1 function (PP3 and BP4 not met). This variant resides within the RNase IIIb domain of DICER1, a mutational hotspot domain with critical functionality as defined by the ClinGen DICER1 VCEP (PM1_Supporting; PMID: 31342592). In summary, this variant meets the criteria to be classified as Uncertain Significance for DICER1-related tumor predisposition based on the ACMG/AMP criteria applied, as specified by the ClinGen DICER1 VCEP: PM1_Supporting, PM2_Supporting. (Bayesian Points: 2; VCEP specifications version 1.2.0; 07/10/2023)