According to a study, the Alzheimer's gene could affect cognitive health before adulthood

A new study reveals that a gene badociated with Alzheimer's disease can impact the brain, particularly on cognitive health even before adulthood.

A team of researchers at the University of California, Riverside, has discovered that the decline in cognitive health begins earlier in people with Alzheimer's disease.

Apolipoprotein E (APOE) is an important cholesterol carrier that facilitates the transport of lipids and the repair of brain lesions. It conditions cholesterol and other fats and moves them in the blood. The polymorphic alleles of APOE are the main genetic factors of the risk of Alzheimer's disease.

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The APOE4 gene linked to Alzheimer's disease

There are three main types of APOE. The APOE4 allele exists in about 15% of the population. In fact, people with the APOE4 allele are three times more likely to develop Alzheimer's disease than people with the more common APOE3 allele. On the other hand, the APOE2 allele reduces the risk of AD.

Previous knowledge showed that the gene was badociated with changes in cognitive abilities, which are evident as soon as the person reaches middle age.

APOE carriers scored lower than IQ tests

But the new study published in the journal Neurobiology of Aging, the researchers said that people with the APOE4 gene had lower IQ scores during childhood and adolescence. In addition, the impact on girls was stronger than that of boys.

"Our results suggest that the cognitive differences badociated with APOE may appear early and be amplified later in life. If this is the case, childhood is a key period of intervention to invest and increase reserves. The effects of APOE on cognition from childhood to adolescence, the researchers said in the study.

To arrive at their results, the researchers badyzed data from the longitudinal study of twins and the Colorado adoption project, dating back three to four decades. These studies focused on genotyping 1,321 participants aged approximately 6.5 to 18 years. During the course of the study, there were three IQ tests between childhood and adolescence.

They found that individuals with the APOE4 allele scored lower than IQ tests by 1.91 points. In addition, researchers have stated that one person can wear up to two APOE4 alleles. The more a person has alleles, the greater the impact on his IQ performance.

By gender, men scored 0.33 points lower on IQ tests, while girls surveyed scored nearly 3 points lower for each APOE4 allele. The results also show that reasoning was the trait most affected by the gene.

According to the researchers, although the IQ score difference is small, it can affect a person's cognitive abilities in the long run. The carrier of APOE4 is aging and, over the years, the gene influences my progress.

What is the cognitive reserve?

Cognitive reserve refers to the brain's ability to solve problems and solve solutions. The cognitive reserve theory states that people with reduced cognitive reserve may have more problems with disease tolerance as they age.

Some studies have also shown the link between low IQ in children and amplified biological aging, such as cell and tissue damage and injury, and cardiovascular disease even before reaching age 65 .

Alzheimer's disease and cognitive health

Alzheimer's disease is a neurodegenerative disease that affects a person's cognitive abilities. First, it affects memory and thinking skills, but as the disease progresses, a person's ability to perform simple tasks can be affected. In most people with Alzheimer's disease, symptoms begin in mid-sixties, but in some cases the disease may begin sooner.

Worldwide, it is estimated that 44 million people live with Alzheimer's disease or a related type of dementia. In the United States, about 5.5 million people have Alzheimer's disease, making it the sixth leading cause of death in the country.

There is still no exact cause of Alzheimer's disease, but many experts say that age is the best-known risk factor for AD. However, people with a family history of AD have a higher risk of developing the disease. In addition, the presence of certain genes can also increase the risk.

Some studies have also shown that changes in the brain may occur years before the onset of symptoms. In some studies, however, diet, environmental factors, and education can also play a central role in the development of AD.