NM_000179.3:c.3602_3606delinsAA is an in-frame deletion-insertion in MSH6 exon 7, resulting in the substitution of leucine 1201 and methionine 1202 with a single glutamine residue (p.Leu1201_Met1202delinsGln).¹ This variant is absent from gnomAD v4.1, v2.1, and gnomAD-Canada, meeting the MSH6 VCEP PM2_Supporting threshold of allele frequency <0.00002 (1 in 50,000 alleles).² The variant is absent from ClinVar with no submissions from any laboratory.³ No functional data, segregation data, tumor phenotype data, or literature reports are available for this variant. The variant has not been tested in any MSH6 VCEP-calibrated functional assay.⁴ PVS1 is not met because this in-frame delins does not introduce a premature termination codon and does not meet any PVS1 rule under the MSH6 VCEP specification (v2.0.0), which requires a nonsense, frameshift, or canonical splice variant.⁵ With only PM2_Supporting met and no other criteria applicable, the variant is classified as a Variant of Uncertain Significance under the ClinGen InSiGHT MSH6 VCEP combination rules (v2.0.0).⁶