Three prominent Democratic presidential candidates have their preferred gender pronouns in their Twitter bios as of Monday, and a fourth added his pronouns after an inquiry from the Daily Caller News Foundation on Tuesday.

Former Housing and Urban Development Secretary Julian Castro’s bio declares “He/Him/Él,” New York City Mayor Bill de Blasio’s bio says “He/him” and Massachusetts Sen. Elizabeth Warren’s bio says “She/her.” Former Colorado Gov. John Hickenlooper’s bio says “He/Him/His” as of Tuesday.

“We got your inquiry. Check the Governor’s Twitter bio — you’ll find it’s been updated with his preferred pronouns,” Hickenlooper spokesman Mark Ranneberger told the DCNF in an email Tuesday. Hickenlooper’s bio did not have the information on Monday.

Castro was the first candidate to add his preferred gender pronouns to his Twitter bio on July 1, his spokesman Sawyer Hackett told the DCNF in an email Monday.

Preferred gender pronouns include, but are not limited to, gender-binary terms like “he” and “she.” Groups like Amnesty International recommend introducing yourself with your preferred gender pronouns and asking new people what pronouns they use, remembering not to “assume how they identify or what their pronouns are.” (RELATED: Here’s Who Is Going Head-To-Head Each Night Of The Upcoming Democratic Debates)

De Blasio’s city adopted a law in 2015 that protects individuals from discrimination based on gender expression or identity.

Campaigns for Colorado Sen. Michael Bennet, former Vice President Joe Biden, New Jersey Sen. Cory Booker, Montana Gov. Steve Bullock, South Bend, Indiana, Mayor Pete Buttigieg, former Maryland Rep. John Delaney, Hawaii Rep. Tulsi Gabbard, California Sen. Kamala Harris, former Colorado Gov. John Hickenlooper, Washington Gov. Jay Inslee, Minnesota Sen. Amy Klobuchar, former Texas Rep. Beto O’Rourke, Vermont Sen. Bernie Sanders, activist Tom Steyer, author Marianne Williamson and entrepreneur Andrew Yang did not immediately respond to the DCNF’s inquiries.

Buttigieg is the only major Democratic candidate who identifies as a member of the LGBTQ community.

Response from Warren’s campaign will be added if received.

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