A gay group has praised Grey’s Anatomy bosses for representing a lesbian character on primetime TV.

The Gay and Lesbian Alliance Against Defamation (GLAAD) spoke out after it emerged that Brooke Smith has been dropped from the series. Smith will make her final appearance as Dr Erica Hahn on this week’s episode of the ABC drama, bringing to an end her character’s lesbian relationship with Dr Callie Torres (Sara Ramirez).

A GLAAD spokesperson said: “While we are disheartened that the burgeoning relationship between Callie and Erica has come to an end, the character of Callie, who has now been identified as a lesbian by show creator Shonda Rhimes, remains and her journey continues.

“Because there are so few lesbian characters on network television, we hope that ABC and Grey’s Anatomy will commit to further developing Callie’s character and her relationships, and continue providing this important representation on one of TV’s most-watched shows.”

Smith has revealed that she was “surprised and disappointed” to be told that her character was being axed.

Melissa George has confirmed that she is leaving Grey’s Anatomy.

The 32-year-old, who plays intern Sadie Harris, told Entertainment Weekly that she had chosen to leave, but insisted that she had nothing but praise for the programme.

“I love the show so much. I’ve made some beautiful friends,” she said. “I love T.R. Knight. I love Patrick Dempsey, Justin Chambers… I adore Ellen Pompeo. I think she’s a strong, incredible woman. And Katherine Heigl is the most beautiful creature on Earth.”

The Australian actress joined the ABC show last November, in a deal that reportedly secured her around eight episodes with the opportunity to become a series regular.

However, she revealed that she chose to depart the medical drama in order to “do something else”, adding that her exit “won’t be a big send-off, but it’s really cool what they do”.

A Grey’s insider said: “Melissa’s arc came to a natural end. Everyone at the show adores her. We’re genuinely sad to see her go.”

People.com reports that the star, who plays intern Dr George O’Malley on the show, has asked producers to write him out of the hit US medical series.

A source close to the situation says it is likely the actor’s request will be granted, although reports that T.R. had walked off set and already cleaned out his dressing room are not accurate, according to the star’s representative.

“He has been there every day,” said the spokesperson. “He was at a table read yesterday. He hasn’t said goodbye to anyone.”

People speculates that T.R. – real name Theodore Raymond – wants out of the show due to his character receiving little screen time this season.

“It’s time to move on,” the source said. “It just feels like this is the right time to go.”

ABC, the network who makes the show, had no comment.