When it came time for students to pick genes to study from the genomes of their fellow Puerto Ricans, Alexandra Wiscovitch chose those responsible for hair and eye color. As a modeling teacher, she had noticed her students had a variety of both.
Fellow student Jorge Irizarry Caro's interest in studying medicine, particularly cardiology, helped him select a gene that may play a role in heart attack. Wiscovitch and Caro are among the student researchers mapping the genetic heritage of Puerto Rico, based on the DNA deoxyribonucleic acid in spit samples they have been collecting from local people on beaches, in shopping malls and other public places across the island.
The genetic material they collect contains clues to Puerto Rican ancestry — a mix of African, European and American Indian — susceptibility to disease and prominence of other traits, such as hair and eye color. As a population geneticist, Oleksyk believes "the most interesting thing is how different people came to Puerto Rico and how they brought different genetic characters with them.
This "story of the people" can be applied to understand how individual Puerto Ricans react to environmental conditions and the disease risks they face, he said. The students are approaching their goal of collecting 96 samples from the island's 78 municipalities.
Yashira M. Afanador, a graduate student, has begun the analysis that will lead to detailed maps of ancestry patterns across Puerto Rico. But this ratio varies across the island, with more European background on the west side of the island and more African on the east side.
Whereas that study looked at genetic markers inherited from both parents called autosomal markersearlier work used markers inherited from the mother to find a much larger share of ancestry from Tainos.
This result likely reflects the history of male immigrants marrying the local Taino women.
When the students approach people, these potential donors are particularly interested in research on Puerto Rican heritage. The LGDS project may also help explain why certain diseases, particularly asthma, affect Puerto Ricans more than other mixed populations, such as Mexicans, say those involved.
Ultimately, Caro sees the project as a way to improve health care for Puerto Ricans through personalized medicine"so, if you go to a hospital, they know you are predisposed to heart attacks because of your genetic ancestry," he said. Caro's research focuses on a gene, known as LTA4H.
Materials and methods
Variants of this gene have been shown to increase risk of myocardial infarction commonly called heart attack markedly among African-Americans. Cardiovascular disease has been increasing in Puerto Rico, and is now the second- most common cause of death on the island, according to Caro. Caro looked for specific variants in LTA4H in samples from municipalities with high African ancestry and in others with high European ancestry.
He found these variants did indeed show up at high frequencies in the more African municipalities.
Ancestrydna® traits learning hub
Meanwhile, Wiscovitch has been looking at genes associated with hair and eye colorincluding a variation linked with red hair. While analyzing samples from the east side of the island, she found something surprising.
In the fall, she is planning follow-up research that will incorporate information about the participants' hair color. It is possible that the red hair gene is not expressed in people who have dark hair, she speculated.
Ultimately, the students will develop their own research projects, just as Caro and Wiscovitch did, and seek outside funding to support them, Oleksyk said. LGDS grew out of Oleksyk's experience taking students door-to-door with colleague Juan Carlos Martinez-Cruzado in to recruit participants for the Genomes Project, which is catag rare variation in many populations.
Original article on LiveScience.
Live Science. Wynne Parry.