Researchers at Saar University are developing blood tests to diagnose Alzheimer's
In the future, Alzheimer's can possibly be diagnosed clearly and quickly with the help of a blood test. Scientists at the Institute of Human Genetics at Saar University have successfully identified the neurodegenerative disease using certain signatures in the blood. The test still has to prove itself in clinical studies, but there is hope for a significant improvement in Alzheimer's diagnosis.
“Alzheimer's is the most common form of dementia. There are around 1.4 million people affected in Germany. There should be around three million by 2050, ”the Saarland University reports in a current press release. So far, it has been difficult or even impossible to prove the disease. Alzheimer's diagnosis "is usually a complex undertaking that uses expensive procedures such as computer tomography or psychological tests that test memory and thinking skills," the university said. An early diagnosis is therefore hardly possible, but would be urgently necessary for the benefit of the patient, since so far no cure, but only a delay in the course of the disease in Alzheimer's has been possible. The blood test developed by the research team around Petra Leidinger, Christina Backes and Andreas Keller at Saar University could bring me a significant improvement here. The researchers published their results in the specialist journal “Genome Biology”.
Biomarkers are used to diagnose Alzheimer's. As part of their studies, the scientists looked for so-called biomarkers that can serve as a reliable indicator of Alzheimer's in a blood test. "Biomarkers are molecules with which scientists and doctors can diagnose diseases and predict the course of a disease," explains Leidinger, Backes and Keller. The so-called microRNAs - small nucleic acids found in the blood - are also suitable as such. Petra Leidinger from the Institute of Human Genetics in Homburg an der Saar explained that the microRNAs “are of great interest to medicine because their composition gives a specific signature that can be assigned to a specific disease.” To determine whether If Alzheimer's has specific microRNAs in the blood, the scientists "tested the blood samples from 100 Alzheimer's patients," reports Andreas Keller from the Institute of Human Genetics, who also works for Siemens Healthcare as Director Technology Innovation.
Precision of the Alzheimer's blood test at more than 90 percent The scientists' search for special biomarkers that indicate Alzheimer's disease was quite successful. "In total, we found a different composition in twelve microRNAs than in the healthy people in the control group," reports Leidinger, Backes and Keller. According to the researchers, a test developed on the basis of the biomarkers showed a gratifyingly high level of accuracy. The precision of the test was over 90 percent, which is a very good result for a biomarker. However, "further examinations are required until clinical use is possible," said Cord Stähler, Chief Technology Officer at Siemens Healthcare, in the press release from the Saarland University.
Differentiation from other neurological diseases, sometimes difficult a also other brain diseases sometimes cause symptoms similar to Alzheimer's, the researchers examined in a further step, “whether there are differences in the microRNA signature between Alzheimer's and other neurological diseases. Although Alzheimer's “was clearly differentiated from schizophrenia or depression”, “with other neurodegenerative diseases such as Parkinson's and mild cognitive impairment, the test results were not as precise,” explained Leidinger. Although slight deviations in the biomarkers were found, the researchers have so far not been able to clearly differentiate between Alzheimer's and neurodegenerative diseases. "But this could be improved by the scientists refining the molecular signatures," reports the Saarland University.
Insights into the molecular mechanisms in Alzheimer's According to the researchers, the current search for Alzheimer's biomarkers has also allowed "further insights into the molecular mechanisms in Alzheimer's". Two of the "microRNAs" are involved in processes that lead to the formation of protein deposits (so-called plaques) in the brain of Alzheimer's patients. The plaques are a characteristic feature of the disease. Scientists from the Neurological Clinic at the University Hospital Erlangen, Internal Medicine II at the University of Heidelberg, the Charité Berlin and the Scripps Research Institute in La Jollla, California, were also involved in the study. (fp)