In the largest genome-wide association study to date on Type 2 diabetes, a team of international researchers, co-led by genetic epidemiologist Cassandra Spracklen, from the University of Massachusetts Amherst, had already located 1,289 genetic markers associated with Type 2 diabetes. Recently, 145 were newly identified.
The study's findings were published in February in "Nature" magazine.
"This study is trying to come at understanding diabetes from a genetic point of view," Spracklen said, and what predisposes a person to have a Type 2 diabetes and what may not. "But what's still really important is to know that this is just a piece of the puzzle."
Other studies that point to the connection between the disease and lifestyle and behavior factors are just as important Spracklen said, if not more important than genetics, but there can be an interplay between the two.
When it comes to this type of study, "no matter what the trait is that we're looking at, part of the next step is to figure out how those DNA variants are working to impact your risk for diabetes," Spracklen said.
Researchers look at the DNA variants to see if they are acting directly on a particular protein, and if having too much or too little of that protein increases the risk of diabetes, Spracklen said.
"Is altering the way your body can handle glucose and sugar, so it impacts your insulin?" she added.
One method researchers use is to take the identified DNA variants and make clusters of them, Spracklen said, "that we show are also associated with other traits. So for example we have eight clusters of these diabetes variants. One cluster is also associated with obesity. So those variants are probably acting somehow through your BMI or your weight, or your body composition to impact your risk for diabetes," Spracklen said.
Another example are variants that are related to liver and lipid metabolism, Spracklen explained, so that set of variants is probably working through that sort of mechanism.
Global Genetic Ancestry Groups
The decade long study includes 2.5 million people from around the world. The breakdown of the "global genetic ancestry groups," Spracklen said includes African/African Americans (156,738 or 6.2%), East Asians ( 427,504 or 16.9%), Europeans (1,812,017 or 71.0%), Hispanics (88,743 or 3.4%) and South Asians (50,599 or 2.0%).
People are primarily based where you would expect, Spracklen said, e.g., East/South Asian individuals are in East/South Asian countries, Hispanic individuals are from Latin and Central America, European (“white”) individuals from Europe and the U.S. However, there are populations of people located in different areas. For example, South Asians living in the UK, Hispanic and African Americans in the U.S.
"We're increasing the number of people in the study, which gives us more ability to identify more and more of these genetic variants," Spracklen said, adding that genetic studies for decades have tried to include more individuals of nonwhite ancestry.
According to the International Diabetes Federation, Type 2 diabetes affects and sometimes debilitates more than 400 million adults worldwide.
Food research in western Mass.
Around the U.S., Type 2 diabetes and other nutrition-related health conditions are among the leading causes of death, illness, and healthcare spending.
"Food insecurity is persistent in low-income communities and presents a major barrier to the health and well-being of families and individuals in western Massachusetts,” said Lorraine Cordeiro, a professor of nutrition at UMass Amherst, in an article from the university's College of Natural Sciences.
Produce prescriptions are part of a strategy to promote healthy eating — and are being studied by researchers for how they impact diabetes and other diet-related health conditions.
“Produce prescription programs are a really innovative way to engage hospitals, clinics, and health centers with local farmers and other entities in the food supply chain to improve food access and promote healthy eating," Cordeiro said.
According to UMass Amherst School of Public Health and Health Sciences, the COVID-19 pandemic both exacerbated and helped bring to the fore the problem of food insecurity.
