The tier 1 cohort included BRCA1, BRCA2, and the mismatch repair genes; the syndromic cohort included genes associated with other well-characterized hereditary cancer syndromes (e.g. APC, PTEN, and TP53); and the emerging evidence cohort included genes that are less well-characterized and have uncertain or unknown cancer penetrance estimates (see Supplementary Table 1 for genes included in each cohort). Here, BRCA1 is linked to cancer.