It’s Fluffy — minus the stuffiness.

For $4,000, a San Diego-based biotechnology company is selling “hypoallergenic cats” — genetically engineered felines that don’t cause sneezing, red eyes, and congestion in most allergy sufferers, a new study shows.

About one-third of those on the year-long waitlist for the nearly sneeze-proof kittens are from New York, according to a spokesman for Allerca, the “lifestyle pets” company that produced the cats and began selling them over the summer. Allerca will breed some 500 felines next year and 2,000 in 2008, the spokesman, Steven May, said. The company is studying ways to produce more exotic breeds of cats, in addition to other hypoallergenic pets such as dogs and rabbits.

“A lot of people in Manhattan who don’t need to work — they’ve ordered them, as well as those people who do work and want someone to come home to,” Mr. May said. In addition to New York, demand for Allerca cats has been greatest in urban hubs such as Los Angeles, Chicago, and Dallas, where the pets can spend much of their time indoors.

Due to a natural genetic variance, one in every 50,000 cats does not carry the Fel D1 glycoprotein, which causes most allergic reactions. Allerca did testing to find cats that were free of allergen and used them to produce hypoallergenic litters, the company said. The animals are not genetically modified.

For Allerca’s four-figure price tag — the cats retail for $3,950 — buyers get a 12-week-old desexed kitten, a certificate of authenticity, and pet health insurance for a year.

A Los Angeles-based allergist, Sheldon Spector, a professor at UCLA, recently completed a study attesting to the “hypoallergenicity” of Allerca cats. For the research, which was not funded by Allerca, people with clinically diagnosed cat allergies were blindfolded and exposed to a room with a regular cat, a room with a hypoallergenic cat, and a placebo room with a lifelike stuffed cat.

An Upper East Side allergist, Wellington Tichenor, said that about 15% of the population suffers from cat allergies of varying acuteness, about twice the amount of people who have dog allergies.

He said time would determine the success or failure of Allerca cats, noting the possibility that people develop new allergies to these genetically engineered cats. “The thing we get concerned about whenever anyone reinvents the mousetrap is that the new mousetrap gets hyped up for an extended period of time, and the hype does not match what the promise was,” he said.

Despite assertions to the contrary, Dr. Tichenor said nonshedding dogs such as poodles, and poodle mixes — labradoodles, goldendoodles, and cockapoos, among others — are not hypoallergenic because they still give off dander, which can irritate those with pet allergies. “It’s certainly possible that people are allergic to some breeds and not others, but we don’t have a good way of assessing that,” he said.

“Like some people who are allergic to dogs look for the nonallergic breeds, I’m guessing people who like cats would do the same thing,” said Sherry Field, an owner of Paws in Chelsea, a pet grooming and boarding facility. “I guess their only other alternative would be to live on Benadryl or antihistamines all the time. I have some clients who do.”