On Oct. 28, 2013, Columbia University Medical Center announced publication of a Meta-analysis of 74,046 individuals that identified 11 new susceptibility loci for Alzheimer’s disease. The findings, published in Nature, stem from the largest international study ever conducted on this disorder, which causes gradual memory loss and other forms of cognitive decline in older people. The study, conducted by dozens of researchers through the International Genomics of Alzheimer’s Project (IGAP), was created in 2011.

None of the 11 new genes has as strong an  effect on Alzheimer’s as the APOE4 gene, which was linked to the disease in the 1990s. APOE4 accounts for about 20 percent of cases, while the strongest of the new genes accounts for, at most, 8 percent of cases.

The significance of the discovery lies instead in the number of possible new drug targets revealed by the study, including some that are involved in processes never before considered in Alzheimer’s.

Other new genes uncovered by the group are related to processes in the brain that are well-known contributors to Alzheimer’s, including the processes that lead to the build-up of toxic amyloid beta and tau deposits, or help confirm newer ideas such as inflammation. The identification of new genes involved in these processes may ultimately lead to new drugs.

What’s most needed now, the investigators say, is an intense effort to understand the precise roles of all 22 genes in the development of Alzheimer’s disease.