NEW YORK — For families who have searched years for missing loved ones, donating a sample of their DNA is often a last, desperate act to confirm their worst fears.

New York City’s medical examiner is leading a nationwide effort to collect genetic material and match it with unidentified human remains. It’s a way to finally give family members some answers and maybe some solace.

‘‘People will not rest without answers, at least some answers,’’ said Dr. Barbara Sampson, the city’s chief medical examiner.

Over the last decade, thousands of DNA samples have been donated to the city’s medical examiner’s office.

Most include swabs of saliva from close relatives, but also DNA taken from items used by the missing persons themselves, including toothbrushes, combs, razor blades, and, once, even a sanitary napkin.

They have led to the identification of about 50 missing people each year, all of whom had been found dead.

But for many who have submitted samples, the wait continues.

Associated Press