JEFFERSON CITY -The Missouri House has cleared for final approval a measure that would mandate insurance coverage for autism spectrum disorder in a voice vote late Tuesday evening.

The bill, sponsored by Rep. Dwight Scharnhorst, R-St. Louis County, would designate up to $36,000 annually from insurance providers for children ages 18 and under diagnosed with autism.

Scharnhorst also added an amendment in response to concern that the legislation would raise insurance premiums at the cost of small business owners. The House passed his amendment - granting small employers a waiver - allowing them to opt out of the provisions if their insurance premiums jumped 2.5 percent or more during a calendar year.

"It is the last thing in the world that I want to do, as a small business owner myself since 1981, to harm small businesses," Scharnhorst said.

Those with an individual insurance policy would not be mandated to obtain autism coverage, but could opt to if desired.

Much of the debate centered around an amendment proposed by Rep. Rob Schaaf, R-St. Joseph, that called for an expansion in Medicaid coverage for every child with autism, whether they were insured or not.

The original bill currently covers only those children who already have health insurance, which according to Schaff is "only 27 percent of the kids who need it." Schaff's estimated his amendment would cost the state around $200 million in fifteen years.

"If we believe children in the state of Missouri need to have autism coverage, we need to give it to all of them," Schaff said. "We can't pick winners and losers."

Scharnhorst spoke out in opposition to Schaaf's amendment, and said he feared the added cost would doom the bill, one he said "will eventually be one of the best bills on autism in the United States today."

"The weight of what you're trying to do here will doom this 27 percent of children you're trying to help," Scharnhorst said. "I think it's a gamebreaker. We've come too far, and fought too hard."

Schaaf's amendment was ultimately voted down, with 87 representatives opposed and 65 in favor.

Sharnhorst's bill, without Schaaf's amendment, was approved by voice vote around 9 p.m. Tuesday.

"This is one of the most significant autism bills in the country," said Speaker Pro Temp Brian Pratt."Missouri should be proud."

The House must vote to approve the bill one more time before it can be moved to the Senate.

Sen. Scott Rupp, R-St. Charles, has proposed separate legislation in the Senate requiring insurance coverage of autism. The Senate version also calls for the same small business exemption, but would require insurance policies to cover $55,000 per year of therapy for children 20 and under.

A bill requiring coverage of autism passed the Senate last year, but was held up in the House.