A medical research conducted on mice discovered what the possible cause for brain cells damaging can be. The study was led by Professor William Mobley, director of the Neuroscience Institute at Stanford University and investigated by comparison mice with three copies of a certain gene found on chromosome 21 and mice with only two copies of the same gene.

The gene studied is called the amyloid precursor protein gene (App) and the results showed that mice with three copies of App have larger neurons than the ones with two copies of the gene. This led the medical team to the conclusion that App damages and destroys neuronal cells by blocking the signaling and connections formed among brain cells. This death of synapses in the brain results in the poor mental health of people that suffer from Alzheimer and Down's syndrome.

Down's syndrome is a condition resulting from a chromosome abnormality that usually is related to the appearance of an extra chromosome (instead of 2, there are 3 copies of chromosome 21.) The symptoms include mental retardation, from mild to severe degrees, hearing loss, speech impairment, learning difficulties, heart and lung problems and also leukemia. Also, the condition is characterized by distinctive facial features (slanted eyes, flat face, short stature etc.).

Down's syndrome and Alzheimer malady are very much alike, as Down's syndrome can lead to Alzheimer and dementia mostly in individuals over 40.

The fact that a mutation in the amyloid precursor protein gene leads to Alzheimer was already known, but Professor William Mobley claims that the present study has achieved further information in how the gene actually works, provided the fact that three copies of App cause a decline of mental health as compared to only two copies. "There are all of these genes on chromosome 21, and undoubtedly all of them contribute in some way to these changes that you see in people with Down's syndrome. The challenge is to say can you find specific abnormalities linked to specific genes," he stated.
Further studies are intended to be carried out in the near future in order to find out how the mechanism of the "damaging" App gene really works. Afterwards, the experts are determined to use the information for preventing and even curing Down's syndrome and associated mental disorders: "If we can decrease the expression of this gene we may be able to provide something more than supportive care to people with Down syndrome," neurologist Mobley said.

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