Currently, Alzheimer’s disease and other dementias are typically detected and diagnosed through memory and cognitive tests or MRI and PET scans of the brain, which can show evidence of tau or amyloid buildup. But with researchers learning more about different Alzheimer’s biomarkers, a blood test may be a sufficient diagnostic tool in the future.
In a new study out of the University of California San Diego, researchers discovered a new biomarker associated with Alzheimer’s disease—high blood levels of RNA from a gene known as PHGDH.
PHGDH produces RNA—a nucleic acid located in all cells that carries DNA instructions to manage proteins—as well as other proteins associated with brain development in children and young people. The researchers found that about two years before a participant was diagnosed with Alzheimer’s, they showed a significant increase in PHGDH RNA production.
The researchers hope pinpointing this biomarker in a blood test could lead to earlier detection of neurodegeneration.
“Several known changes associated with Alzheimer’s disease usually show up around the time of clinical diagnosis, which is a little too late,” Sheng Zhong, a professor of bioengineering at UC San Diego and a lead author of the study, said in a news release.
“We had a hunch that there is a molecular predictor that would show up years before, and that’s what motivated this study,” Zhong continued.
Past research has examined the potential of blood tests in helping to detect Alzheimer’s earlier. In one recent study, researchers developed a blood test that can find Alzheimer’s biomarkers in plasma–the liquid found in blood.
Another team of researchers from French company Amoneta Diagnostics have been working on developing another blood test that also looks at RNA in the blood.
But the researchers of the latest study have a few more steps to go before they can develop a proper blood test. They’ll need to further test the PHGDH biomarker in studies to ensure it can identify the disease in earlier stages consistently.
“We are not yet calling this a verified blood test for Alzheimer’s disease,” Zixu Zhou, another author of the study, said in the news release. “Nevertheless, our data, which were from clinically collected samples, strongly support the discovery of a biomarker for predicting the development of Alzheimer’s disease.”