A group of Democratic senators is asking the FDA to lift the ban on gay men donating blood.

Led by Sen. John KerryJohn Forbes KerryKerry: Trump's rhetoric gave North Korea a reason to say 'Hey, we need a bomb' Russian hackers targeted top US generals and statesmen: report Trump officials to offer clarity on UN relief funding next week MORE (D-Mass.), the lawmakers wrote a letter to FDA Commissioner Margaret Hamburg on Thursday calling the ban discriminatory and unwarranted.

The rule was put in place in 1983 to prevent HIV-tained blood from entering the nation's blood supply. The senators argued Thursday that modern HIV tests have made a blanket ban on gay donors unnecessary.

"We live in a very different country than we did in 1983," they wrote. "Today, the high-risk behaviors associated with HIV contraction are more fully understood and dramatic technological improvements have been made in HIV detection."

Moreover, the senators argue that the rule is plainly discriminatory, since heterosexual donors who have engaged in risky sexual behavior aren't as strictly screened.

"[P]rospective donors who have engaged in heterosexual sexual activity with a person known to have HIV are deferred for one year. At the same time, male donors who engaged in protected homosexual sexual activity with a monogamous partner 26 years ago are deferred for life," they wrote.

A group of 11 House Democrats, led by Rep. Mike Quigley (D-Ill.), petitioned the FDA in December to drop the ban..

Kerry led a successful effort earlier this year to lift a travel ban on HIV-positive individuals entering the United States.

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