Variable cut cause dementia

For most species, stop childbearing would mean the end of life, and mankind is a rare exception. Not only taking care of elder generations, but also to teach a lot of natural and social experience. With age, the human cognitive levels will gradually decline, making older people has now become the most in need of care in the community of a large group. So, how to solve the neurodegenerative disease caused cognitive impairment is an important issue currently affecting human society. As we gradually move towards national aging society, this problem is particularly worth considering.

Alzheimer's disease (commonly known as Alzheimer's disease) is representative of a class of neurodegenerative diseases, aging of Alzheimer's disease is unique to humans. Previous studies have found a close link between the incidence of human CD33 gene promoter region of some genetic characteristics with Alzheimer's disease. CD33 has two types of shear mode, and can produce two types of protein: a class outside the 2nd exon, called CD33M, another class without the exon, called CD33m. Studies have shown that the incidence of Alzheimer's disease for CD33M has an important role. In this regard, Ajit Varki from UCSD Study Group compared the difference between human and chimpanzee CD33 gene, and based on this to find the other associated with the onset of Alzheimer's disease gene. The results were published in "PNAS" the latest issue of the magazine.

Because other primates, including humans closest relationship with chimpanzees, are not cases of dementia, the authors compared the differences between humans and other primates CD33 of. The results showed that about 0.21 percent of protective CD33 sequence (CD33m) in humans. In addition, expression of human and chimpanzee brain CD33m fairly level, but the expression of human CD33M is four times the chimpanzees. This result suggests that, at a certain stage of evolution, the expression of the human body CD33M upregulation occurred and led to the generation of Alzheimer's disease, in which the cause is not clear.

In addition, the authors also analyzed the expression of other genes, the results show that the incidence of Alzheimer's disease gene include APOE, AGT, SCG2, etc., have some contact. Based on this, we can use the means of gene diagnosis and early detection of patient CD33M CD33m, thus more accurately predict Alzheimer's disease risk, and we can take a method of gene therapy by introducing CD33m or artificially low expression levels CD33M way to treat patients with Alzheimer's disease.