These conditions—HBOC syndrome (associated with BRCA1 and BRCA2 genes), Lynch syndrome (LS) (associated with MLH1, MSH2, MSH6, and PMS2 genes), and FH (associated with APOB and LDLR genes)—are collectively identified as “Tier 1” conditions. Here, MSH2 is linked to Hereditary breast and ovarian cancer syndrome.