The mechanism whereby the GMB influences amyloidosis appears to be independent of changes in amyloid beta processing machinery, as there seems to be minimal whole brain changes in amyloid precursor protein (APP) or beta-secretase 1 (BACE1) between abx-treated mice or GF mice and conventionally raised non-treated mice [5, 6, 14]. The gene discussed is BACE1; the disease is amyloidosis.