A studio published this month in la Nature magazine has revealed the second case in the world of resistance against Alzheimer’s disease. He is a Colombian who presented a genetic variant that grants this protection to early-onset hereditary Alzheimer’s.
The man, already deceased, did not have cognitive problems until he was 67 years old and carried the PSEN1 gene, which gave him a predisposition to autosomal dominant alzheimer (ADAD).
Who therefore this gen has a mild cognitive impairment at an average of 44 years, dementia at 49 and die from complications around 60 years.
The investigators detailed that the previous case was a woman who remained without cognitive deterioration for almost 30 years after the expected age of clinical onset.
The genetic variant now identified and called Reelin-COLBOS is produced in the RELN gene, which encodes the reelin protein, which plays a fundamental role in the regulation of development and the function of brain cells.
La naturaleza made “an exceptional experiment with these subjects: the dotó of a gene that causes alzheimer’s disease and, at the same time, of another gene that protected them from the symptoms of the disease for more than two decades”, highlighted Francisco Lopera, director from the Neurosciences Group at the University of Antioquía and co-author of the new study.
The solution involves “imitating nature by developing therapies that mimic the protection mechanism of these genetic variants in subjects at risk of suffering from the disease”, added the researcher in a statement from Mass General Brigham, a network of hospitals based in Boston (U.S).
The team analyzed clinical and genetic data of some 1,200 people from Colombia carrying the Paisa mutation, which identified this man who remained without cognitive impairment until he was 67 years old, progressed to moderate dementia at 72 and died at 74.
Two of the characteristics of Alzheimer’s are the presence in the brain of beta amyloid peptide plaques and the formation of tau protein eggs.
After comparing the characteristics of both people, the team saw that they showed a generalized amyloid pathology in the brain.
However, there was a limited aggregation of tau protein in the entorhinal cortex, a brain region that is characteristically affected in the first clinical phases of Alzheimer’s.
The researchers suggested that the Reelin-COLBOS variant might be more effective in limiting tau protein aggregation and egg formation.
Although it cannot be completely ruled out that other factors, including additional genetic variants, have contributed to the patient’s resistance to symptoms, experimental tests in preclinical studies strongly implicate this variant. (I)
