Science Daily (2011) claims that ‘four new genes that play significant roles in Alzheimer’s disease were discovered by the researchers from a consortium of 44 universities and research institutions in the United, States, including Rush University Medical Centre. Each of the genes may have link to the association of late-onset Alzheimer disease (LOAD)’.
During the research, more than 11,000 of elderly were analyzed with Alzheimer’s disease and most of them were at the same age without any dementia symptoms. What is dementia? Dementia is not a specific disease, but it refers to the declination of mental ability. Overall, dementia leads to the symptoms of mental disability which affect a person’s daily activity performances. One of the most common types of dementia is known as Alzheimer disease.
The causes of Alzheimer disease are still undefined. However, researchers believe that there are multiple factors which lead to this disease. Genetic factor is the trespass of Alzheimer’s disease. One of the genes that impact the most is the gene for Apolipoprotein, which identified over 15 years ago. Apolipoprotein E is a protein involved in the transportation of various lipids (cholesterol) to the bloodstream. There are few major form of APOE gene, which includes APOE-e2, APOE-e3 and APOE-e4. One of the greatest risk factor to develop Alzheimer’s disease is the APOE-e4. In the present studies, there are four new genes that been discovered lately by the researchers that involve in the association of Alzheimer’s disease. Membrane-spanning 4-domains (MS4A) is a protein coding that is common with the interaction of Alzheimer disease. Apart from that, researchers had also found that CD2-assocoiated protein (CD2AP) may contribute to the Alzheimer’s disease development. CD2AP is another protein coding helps in actin cytoskeleton regulation. Besides, EPHA1 is the protein coding found to be belongs to the subfamily of the protein tyrosine-kinase family. “The ephrin receptors are divided into 2 groups based on the similarity of their extracellular domain sequences and their affinities for binding ephrin-A and ephrin-B ligands.” (NCBI, 2011) Lastly, protein coding CD33 is a transmembrane receptor for the myeloid cell. It is usually considered myeloid-specific, but it can also be found on some lymphoid cells. A genome-wide survey was carried out for the genes mentioned above among the Caribbean Hispanics. The survey concluded that the risk of developing Alzheimer’s disease has interaction with gene MS4A, CD2AP, EPHA1 and CD33.
The determinations of these new genes are essential in order to discover the drugs treatment for Alzheimer’s disease. Furthermore, genetic studies can help researches to figure out any risk of pathogenic development that occur in the brain before the appearance of any symptoms. One of the most significant aim for this studies is to identify the high risk individuals in developing Alzheimer’s disease, and taking any preventive measurement when it’s necessary.
1) Alzheimer’s Association 2011, ‘ 2011 Alzheimer’s disease facts and figures’, Alzheimer’s and Dementia, vol. 7, Issue 2, pp. 208-244.
2) T. Pirttila, H. Soininen 1996, ‘Apolipoprotein E (apoE) levels in brains from Alzheimer disease patients and controls’, Brain Research, vol.722, Issues 1-2, pp. 71-77.
3) Adam Naj 2011, ‘Genome-Wide association study of late-onset Alzheimer disease identifies disease-associated variants in MS4A4/MS4A6E, CD2AP, CD33, and EPHA1’, Alzheimer’s and Dementia, vol. 7, Issues 4, pp. 191.
4) Science Daily 2011, Four New Genes for Alzheimer’s Disease Risk Identified, viewed 17 March 2012 http://www.sciencedaily.com/releases/2011/04/110403141329.htm
5) US National Library of Medicine National Institutes of Health 2011, The membrane-spanning 4-domains, subfamily A (MS4A) gene cluster contains a common variant associated with Alzheimer's disease, viewed 17 March 2012 , http://www.ncbi.nlm.nih.gov/pubmed/21627779
6) US National Library of Medicine National Institutes of Health 2011, MS4A4E membrane-spanning 4-domains, subfamily A, member 4E [ Homo sapiens ], viewed 15 March 2012, http://www.ncbi.nlm.nih.gov/gene/643680