With the goal of finding new drug targets, researchers from the University of Miami partnered with physicians in Puerto Rico, Peru and Africa, searching for new genetic factors that contribute to the degree of risk and protection against the disease.

Through a study, focused on the Puerto Rican population, which represents the second largest Hispanic group in the continental U.S. (12.5%), it was found that while in the country as a whole, Alzheimer's is the 5th leading cause of of death in people over 65 years of age, in Puerto Rico it ranks 4th in the same age group.

Research Background

Considering how more than 30 years ago Alzheimer's genetic studies were carried out in non-Hispanic white populations of European descent, without taking into account communities of Hispanic and African descent, Margaret Pericak-Vance, a pioneer in the genetic study of the disease, took charge of involving these populations in the research.

A variant of the APOE gene, APOE4, is considered the most significant genetic risk factor for late-onset Alzheimer's disease, and most studies initially only included people of European ancestry.

“A genetic target, which drug companies are showing interest in, is twice as likely to be successful therapeutically than nongenetic targets,” Pericak-Vance told NBCNews.

Currently, Pericak-Vance leads the Hussman Institute, which is building a large genetic database to investigate aspects of Alzheimer's and genetic variations between Hispanic and Afro-descendant communities, with the goal of filling an important gap in minority research that could play an important role in the development of drugs for the disease.

Read more about what are researchers are doing: https://t.co/JSwAomo7vV pic.twitter.com/hX0Q2rw9TM

— John P. Hussman Institute for Human Genomics (@HIHGatUM) December 22, 2022

The Hussman Institute, one of the major programs funded by the National Institute on Aging, part of the U.S. National Institutes of Health, has received more than $100 million for research in this subject since July.

For her part, Dr. Katrina Celis, a Venezuelan associate scientist at the Hussman Institute, who has spent the last 13 years focusing on genetic research, highlighted: “Coming from an underdeveloped country, I faced and understood the need for inclusion and representation of diverse populations in genetic research. I have mainly focused on increasing genetic research participation from diverse populations, specifically from Hispanic Latino communities.”

Celis is collaborating with Dr. Briseida Feliciano-Astacio, a neurologist and principal investigator at the Universidad Central del Caribe, in Bayamón, Puerto Rico, where they study large families in Puerto Rico and what they call "multiple families," which it means they have more than two or three people with Alzheimer’s.

A variant that only exists among Hispanic Caribbeans

Considering that Puerto Ricans are a mixed population, and their genetic ancestry is comprised primarily of European, African, and Native American or Amerindian ancestry, new studies have focused on African origin.

“We identified that the particular region that harbors this variant that is associated with Alzheimer’s disease risk lies on the African ancestral background. However, that particular variant has only been found in Caribbean Hispanic individuals, mainly of Puerto Rican descent, which is known in the genetic world as a founder mutation, meaning something happened in the island after the colonization that created this sort of variant within the genetic information of these individuals,” said Celis. 

There are about 6 million people in the United States with Alzheimer's, and its prevalence is projected to rise to nearly 14 million by 2050. It is the most common form of dementia in the elderly and slowly destroys memory and thinking skills. There is no cure, and available treatments have limited effectiveness.