Purpose: To assess the contribution of germline pathogenic variants (PVs) in population-based series of breast cancers and the best strategy to improve detection rates. Methods: Three cohort studies were utilized, including a hospital-based series identified from new UK mainstream testing criteria (group-1), offering testing to all women (group-2-BReast CAncer [BRCA]-DIRECT), and a Greater Manchester cohort study recruited from the mammography screening population (group-3-Predicting Risk of Cancer at Screening). DNA samples from women with breast cancer were sequenced for PVs in BRCA1, BRCA2, and Partner and Localiser of BRCA2 (PALB2). The Manchester score (MS) was used at different points thresholds. Current mainstream criteria include women diagnosed