Alzheimer’s disease: Main culprit is ‘apoE4 gene’

Alzheimer’s disease invades slowly and stays on with the patient as a life partner. The silver lining is that for the perceptive person the initial symptoms of Alzheimer’s disease are quite obvious to be missed out.

Medical scientists have identified the major cause of Alzheimer’s disease. Certain mutations in genes lead to this progressive brain disorder.

ROLE OF GENES & FAMILY HISTORY IN ALZHIEMER’S DISEASE ESTABLISHED

The presence of particular genes has been linked to Alzheimer’s disease. Medical detectives have identified the role of such genes in increasing the risk of the carrier (read patient) in contracting Alzheimer’s disease. This revelation has also gone a long way in the invention of medicines to cure or at least lessen the effects of the progressive brain disorder on the patient.

The genetic researches have come up with the following result:

(a) The main agent causing Alzheimer’s disease has been identified as the ‘apoE4 gene’.
(b) The ‘apoE4 gene’ occurs rarely.
(c) The late-onset Alzheimer’s patients are carriers of this ‘apoE4 gene’.
(d) It has also been established that the mere presence of the ‘apoE gene’ is enough to increase the risk of the carrier insofar as the Alzheimer’s disease is concerned.
(e) The ‘apoE gene’ is a typical adaptation of the apolipoprotein E gene.
(f) This ‘apoE gene’ is found on chromosome 19.
(g) However, there are other versions of the ‘apoE gene’ – like the ‘apoE3′. Carriers of this and other versions are less vulnerable to Alzheimer’s disease.

GENE VARIATIONS LEAD TO ALZHEIMER’S DISEASE

Genetics scientists have further pinpointed that differences or variations in genes particularly on chromosomes 1, 10, and 14, can also increase the risk of the carrier (read person) to Alzheimer’s disease.

For instance, gene variations on chromosomes 1 and 14 may lead to mutations in the ‘presenilins’ proteins. Such mutated proteins increase the activity level of the gamma secretase enzyme which splices the amyloid precursor protein that destroys the brain neurons causing Alzheimer’s disease. The amyloid precursor protein is present in plaques.

It has also been found that Alzheimer’s disease is significantly frequent among certain groups of people. This has spurred on investigations into the possible genetic links. Therefore, intensive studies into family histories of patients have shown that people from families having a history of Alzheimer’s disease are more prone to this progressive brain disorder.