In 1994, the discovery of the BRCA1 gene, which lead to the development of blood tests to search for inherited mutations linked to a higher risk of breast and ovarian cancer, was a monumental achievement not only for the prevention of breast cancer, but for the general field of medicine. Today, researchers at the Gladstone Institute in San Francisco have found a link between the depletion of BRCA1 protein, a product of the BRCA1 gene, to the development of Alzheimer???s disease. Their findings suggest the lack of BRCA1 protein in neurons impairs brain cell function, resulting in a decline in cognitive function, a hallmark of Alzheimer???s disease.
Lennart Mucke, a professor of neuroscience at the University of California-San Francisco, and affiliate of the Gladstone Institutes, remarks, ???It???s extremely interesting that one molecule can be critically involved in two apparently opposing conditions: cancer, in which too many cells are born, and neurodegenerative disease, in which too many brain cells die off.???
The BRCA1 protein helps to repair breaks in DNA that occur when a cell is injured. When DNA is unable to be repaired, due to mutation or alteration in the gene, cells are more likely to develop mutations themselves which can lead to breast and ovarian cancers. Neurons in particular may be more likely to suffer from these DNA breaks which are hypothesized to disrupt the functions encouraging learning and memory.
The researchers at Gladstone genetically engineered mice to have neurons with depleted levels of BRCA1 protein. The study observed DNA damage and neuron shrinkage in the brains of the mice, resulting in the animal???s learning and memory decline. Noting the similarities to Alzheimer???s disease, the researchers analyzed post-mortem brains of Alzheimer???s patients and discovered the levels of BRCA1 were 65-75% lower than in the brains of those not affected by the disease. The researchers are now questioning whether increasing levels of BRCA1 protein could possibly prevent or reverse the effects of Alzheimer???s.
Professor Mucke concludes, ???The functions of BRCA1 in the brain remain to be fully elucidated, but our findings suggest that it may play an important role in supporting critical brain functions in both health and disease.???
For more information, read the study here – http://www.nature.com/ncomms/2015/151130/ncomms9897/full/ncomms9897.html