The researchers filed yearly disclosure forms showing they received a total of $120,000 from several drug companies. But they admitted to receiving more after Sen. Charles Grassley (R-Iowa) sought added documentation in March.
"Obviously, if a researcher is taking money from a drug company while also receiving federal dollars to research that company's product, then there is a conflict of interest," Grassley said in a statement.
The U.S. National Institutes of Health requires researchers to disclose when they receive at least $10,000 from companies whose products are being used in studies. When researchers fail to do so, institutions can lose their federal funding, Bloomberg reported.
Harvard Medical School and Massachusetts General Hospital don't allow researchers to work on a company's product if the researchers get more than $20,000 a year from the company.
Scientists Identify Gene Linked to Enlarged Heart
A new genetic cause of enlarged heart has been identified by an international team of scientists, who said their finding could lead to new treatments.
In research with rodents and humans, the scientists found that the gene osteoglycin (Ogn) regulates the growth of the heart's left ventricle, it's main pumping chamber. When Ogn behaves abnormally, the heart can become enlarged, BBC News reported.
The study appears in the journal Nature Genetics.
It was already known that irregular heart growth can be caused by obesity, high blood pressure and strenuous exercise, but the influence of genes is largely unknown, BBC News reported.
"But, now that we are unraveling how genes control heart growth, we can gain a better understanding of common forms of heart disease. This could lead to new and more effective ways of treating people," said researcher Dr. Stuart Cook.