Marion Grodin thinks comedy is in the genes.

"I think they're going to find a molecule with a smile on it," she says, only half-jokingly. Her father, Pittsburgh-born actor Charles Grodin, was funny. Still is.

Her late mother? "Brilliantly funny." Marion's paternal grandmother? "Hilarious."

True, she listened to Richard Pryor and Lenny Bruce records as a child and observed Woody Allen at the next table at Elaine's (as her dad cracked wise), but she suggests, "I think you're coded for it."

After all, she says, look at those studies of identical twins separated at birth and found to be wearing the same pink sweater, hairdo and bauble earrings years later.

Grodin is in town for the Pittsburgh Jewish-Israeli Film Festival -- she will appear Thursday before the 7:30 p.m. showing of "Making Trouble" at the SouthSide Works Cinema -- and for a couple of gigs (tonight at 8 p.m.) at the Improv at the Waterfront.

Although Marion still has relatives in Pittsburgh, she doesn't visit as much as she would like.

"I love Pittsburgh, and my joke is that all roads lead back to Pittsburgh. You're talking to anyone for more than 26 minutes, inevitably they say, 'Are you from Pittsburgh?'" because they have a connection, too.

"My mom and dad met at the Pittsburgh Playhouse when they were, like, 20. They were these two odd, really talented, eccentric actors, and they hooked up and moved to New York City, and my dad became a big star, and they had me, and my mom became a woodworker. She made furniture. ... They lived in a crummy little one-room whatever, and they did what they had to do."

They split up when she was a child, and her mother was gravely ill when Charles Grodin was offered a plum part in "Midnight Run." He said he would pass if Marion needed him. "They're both really, really unusual, amazing people."

A New Yorker who technically lives in New Jersey now, Marion Grodin became aware of her talent as a teenager when she started to socialize with groups of people.

"I was like, huh, I have this gift. I have this magic thing I can do where I say stuff and people laugh hysterically, and it was almost like finding out you had a superpower."

Doing characters and voices from a stoop in Brooklyn, she could make her friends laugh so hard they had to hold their sides.

Today, she has a day job with the nonprofit organization HELP USA (her dad, Martin Short, Regis Philbin and Paul Shaffer will entertain at an April 14 fund-raiser in New York to help homeless veterans) and a nighttime gig performing.

Even in an election year, she's not political on stage.

"I'm very autobiographical. I'm very personal. I'm edgy, very self-revealing. ... I'm not particularly observational in that removed way. I'm very much coming off my own struggles, angst, insecurities."

She describes her act this way: "Improv and working with the crowd, working off the cuff and thinking fast, thinking on my feet and not necessarily even doing material. My favorite gigs are when I don't even go into material."

And Grodin never knows when a show will, against all odds, catch fire. She headlined the Gotham Comedy Club on a recent Wednesday -- a rainy Wednesday, at that -- and yet the house was full, and fans Kevin Bacon and Kyra Sedgwick were surprise additions to the already appreciative audience.

"Every show has its own chemistry. It's a conversation, and every conversation's different."

Unlike her father, who appeared in hits such as "Midnight Run," "Dave" and "The Heartbreak Kid," Marion had no desire to go into movies. "I don't know exactly why, although you'd think it would have come up in my therapy in the last 20 years. But it wasn't really my thing. Stand-up was my thing. ... I like real. My ultimate goal is to have a talk show."

Although strides have been made since the time of Molly Picon or Sophie Tucker, two of the women profiled in "Making Trouble," stand-up comedy is still a boy's club.

"It's still very much patriarchal. There is still very much a widespread feeling -- unfortunately, sadly and so wrongly -- that women aren't funny by a lot of people. I actually get bookers who will say to me, 'We don't book women in that room,' and think it's OK to say that."

What's the difference between that and saying they don't book African-Americans or performers in wheelchairs?

Often, women are missing from a club's lineup or represented by a token female, unless it's a theme show like "Ladies Let Loose" or "Women Gone Wild."

"It's gotta be packs of women in the street. It's like we've escaped, we're on the loose and we're running," she says. "It has to be some theme thing. It can't just be, yeah it's a comedy show, and there are three women and there are three men."

The only way that happens is if it's ... Battle of the Sexes.

Even breakthrough stars on television, from Lucille Ball to Julia Louis-Dreyfus, haven't leveled the playing field.

"It's like any -ism, whether it's sexism or racism or ageism, whatever it is. It's like you drop a rock in the pond and the pond is big, and the rock makes circles that reverberate, but it takes a long time and a lot of rocks till it really affects the whole pond."

But you can count on Grodin to keep lobbing rocks into the pond and trying to make ripples or outright waves.