Are there specific gene mutations that have been identified in Alzheimers or Parkinsons?
A. A number of genes have been identified in Alzheimer’s and Parkinson’s. Some of them cause what is called earlyonset familial autosomal dominance Alzheimer’s disease. Mutations to genes called presenilin 1 and presenilin 2 account for 60% of patients with a familial origin of the disease. A lipid-carrying protein called ApoE4 predisposes people to develop Alzheimer’s disease. But all these mutations account for only 5-10% of the total number of Alzheimer’s patients. Q. Are motor neurons attacked in Parkinson’s disease? A. No. In Parkinson’s, the striatal cells in the substantia nigra are affected. Some of the neurons turn black from oxidation of the neurotransmitter, dopa, which is indicative of oxidative stress. Q. Is oxidative stress a common denominator in many of these pathologies? A. Oxidative stress plays a role. So does brain inflammation, as illustrated by the activation of astrocytes. But are these events early causal agents or tombstones—something that’s happened after the
