Both LRRTM3 and CTNNA3 are located at the genetic linkage peaks for plasma levels of amyloid ß (Aß) identified by our group in extended late-onset Alzheimer’s disease (LOAD) families [2] and for LOAD risk detected in an independent sib-pair study [3], making both genes interesting positional candidate LOAD risk genes. Here, CTNNA3 is linked to Alzheimer disease.