Is there a specific gene that carries Alzheimers?

Alzheimer's is not caused by a single gene, but rather a combination of genetic risk factors and environmental factors. While certain genes may increase the likelihood of developing Alzheimer's, they do not guarantee the disease will manifest. Some variations of genes like APOE4, PSEN1, and PSEN2 have been associated with an elevated risk, but further research is necessary to fully understand the genetic contributions to Alzheimer's.