A senior White House advisor announced Wednesday that the Obama administration supports an end to controversial "conversion" therapies for LGBT people. 

Valerie Jarrett's statement was in response to a White House petition regarding the suicide of transgender teen Leelah Alcorn, whose parents took her to Christian therapists. 

"We share your concern about its potentially devastating effects on the lives of transgender as well as gay, lesbian, bisexual and queer youth," Jarrett said.

"The overwhelming scientific evidence demonstrates that conversion therapy, especially when it is practiced on young people, is neither medically nor ethically appropriate and can cause substantial harm."

Leelah, born Joshua Ryan Alcorn, walked in front of a tractor trailer in Warren County, Ohio in December, and scheduled a suicide note to be posted on Tumblr after her death.

The 17-year-old detailed her desire to transition to a female on her "Satan's Wifey" blog, and the opposition she received from her family. 

"When I was 14, I learned what transgender meant and cried of happiness," Alcorn wrote. "After 10 years of confusion I finally understood who I was.

"I immediately told my mom, and she reacted extremely negatively, telling me that it was a phase, that I would never truly be a girl, that God doesn't make mistakes, that I am wrong."

The teen said her family took her to Christian therapists, pulled her out of school, and kept her off social media. Her death resulted in an outcry from LGBT activists, and a petition to ban conversion therapies. 

The White House said the controversial treatment is banned for use on minors in three states, and similar legislation is pending in 18 other states.

While Jarrett did not explicitly call for a federal ban, National Center for Transgender Equality executive director Mara Keisling said their stance is encouraging. 

"Having President Obama and the weight of the White House behind efforts to ban conversion therapy is so critical in the fight for transgender and LGB young people," she said in a statement. 

"My hope is that when a transgender person's struggle is acknowledged by one of the most recognizable figures in the world, it positively changes the way they view themselves.

"The pseudo-science that propels conversion therapy cannot match the self-acceptance that comes with this kind of change."