WASHINGTON (AP) — The director of the National Institutes of Health, Dr. Francis S. Collins, says he's stepping down.

Collins has led the research center for 12 years. During that time, he has directed research into the human genome and the fight against serious diseases like cancer, Alzheimer’s, diabetes and COVID-19.

The 71-year-old Collins said in a statement that he believes that no single person should serve in his position for too long.

“It’s time to bring in a new scientist to lead the NIH into the future,” said Collins.

President Barack Obama selected Collins as director in 2009. Presidents Donald Trump and Joe Biden asked Collins to remain in the job.

The Bethesda, Maryland-based NIH is the nation’s medical research agency and operates more than two dozen institutes and centers.

In the future, Collins will continue to lead his research laboratory at the NHGRI, which is pursuing genomics, epigenomics and single-cell biology to understand the causes and means of prevention for type 2 diabetes.

Collins’ lab also seeks to develop new genetic therapies for the most dramatic form of premature aging, Hutchinson-Gilford Progeria Syndrome.