Our findings were published in the journals Human Genetics and Neuroscience Letters. It has been determined that the presence of the APOE4 form is a risk factor for developing the disease and is not the cause of the disease. The next two genes found to be linked with the disease were identified in 1995. One of these two genes is now called presenilin 1 and is found on chromosome 14. Many mutations have been found in this gene.
Mutations generally occur in families with very early onset disease.
That is, the symptoms start while the patients are in their 40's. Most of the mutations found thus far seem to be specific for a particular family. One family enrolled in the DNA Bank has one of the mutations described. This finding was published in NeuroReport. The other gene found in 1995 is now called presenilin 2 and is located on chromosome 1.