The ATM NM_000051.3:c.5681_5682del (NP_000042.3:p.(Glu1894AlafsTer9); p.(E1894Afs*9)) variant has been reported in ClinVar and is classified there as pathogenic, including by the ClinGen Hereditary Breast, Ovarian and Pancreatic Cancer Variant Curation Expert Panel.¹ This variant is absent from gnomAD v2.1 and is present only 3 times in gnomAD v4.1 (AF 1.85994e-06; 0 homozygotes), which is below the ATM PM2_Supporting threshold of 0.001% and well below the BS1 and BA1 thresholds.² The variant is a frameshift predicted to truncate ATM at codon 1894, and under the ATM VCEP framework this supports PVS1 because loss of function is an established disease mechanism for ATM; the ATM-specific PM5 truncation rule also applies because the premature termination is upstream of p.Arg3047.³ SpliceAI predicts no significant splice effect for this variant (maximum delta score 0.14), which is below the ATM PP3 splice threshold of 0.2 and above the BP4 benign splice threshold of 0.1.⁴