Alzheimer's disease typically afflicts patients during the later years of their lives, and is most commonly associated with a general loss of cognitive function. For example, there is often progressive memory loss and a general decline in the patient's ability to reason, solve problems, and maintain an even emotional keel. Recent research has led to speculation that as many as 80% of all Alzheimer's cases are genetically transmitted, although environmental factors can lead a patient to contract the disease and also may influence how quickly the patient develops symptoms (Alzheimer's disease may, 2006).
             Genetically-linked Alzheimer's is transmitted in an autosomal dominant mode, which means it is not sex-linked and it will develop even in if the gene is heterozygous (Mullan, et.al., 1995 and Tanzi, 1999). In short, Alzheimer's can be expressed when genes are either homozygous dominant or heterozygous dominant.
             A number of things occur in the brain that cause a person to develop Alzheimer's symptoms. Many Alzheimer's patients experience a sharp decrease in the production of acetylcholine, a key neurotransmitter, and over-production of the protein B-amyloid, which can cause obstructive neuritic plaques to form (Alzheimer's disease, No date). Alzheimer's patients also may experience brain deterioration related to aging, such as neuron or snynaptic loss, which can impair cognitive and neurological function (Alzheimer's disease, No date).
             Generally speaking, the phenotypes of Alzheimer's relate to a loss of cognitive function, although there can be strong psychological and physical components. According to the Mayo Clinic, which has researched and treated Alzheimer's extensively, the 10 warning signs for Alzheimer's are memory loss; difficulty performing familiar tasks; problems with language; disorientation related to time and place; poor or impaired judgment;...