BMPR1A and Familial adenomatous polyposis: Phenotypes other than JPS reported in association with BMPR1A variants to date include FCCTX [7, 29] this study, early-onset colorectal cancer with mismatch-repair proficiency [30], attenuated familial adenomatous polyposis [28, 31]– [32], hereditary mixed polyposis syndrome type 2 [33–35], and combined features of more than one of the above [36].