Carrie Fisher defies genetics. How did this witty, wonderfully talented, albeit seriously troubled, woman emerge from the union of a lecherous moron and, to put it kindly, a bubbly but intellectually challenged Barbie doll?

Fisher tries to explain in the scathingly revealing and very funny one-woman show, “Wishful Drinking” on HBO. If you don’t subscribe, manipulate a friend to invite you over when it’s on, as it often is this month.

Her life arc goes from infancy during the past century’s biggest Hollywood scandal–Eddie Fisher, Debbie Reynolds, Elizabeth Taylor (think Pitt, Anniston, Jolie, she advises today’s audiences)–to iconic status herself (a Pez dispenser, among other knockoffs) as Princess Leia in “Star Wars” and, recently, as the poster girl (seriously) for bipolar disorder in medical journals. “It’s the same as manic depression,” she explains. “Bipolar sounds like a gay bear.”

Fisher, whose father recently died, still lives near her mother who, in a joint interview to promote the special, insists on blaming Eddie for the “disease, which you were unfortunately given by genetic factors, which is your father’s gift to his daughter.”

A preview of Carrie’s bollixed biography can be found in the 1990 movie, “Postcards from the Edge,” based on her novel, in which she is played by Meryl Streep, whose mission in life seems to be portraying every semi-famous woman of our time. (Sample dialogue: Emergency room doctor: “We’re going to have to pump your stomach.” “Do I have to be there?”)

Personal footnote: In Eddie Fisher’s bachelor days, he kept pressing a Hollywood friend of mine to introduce him to Audrey Hepburn. “I couldn’t explain,” the friend said, “that she lived on a different intellectual planet, so I just said she was a Lesbian.”

Soon afterward, when Hepburn married Mel Ferrer, Fisher was upset so “I told him she had gone somewhere for a miracle cure. He believed me.”

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