Marina Sarris

Date Published: June 2, 2026

The SPARK study launched in 2016 with the goal of recruiting tens of thousands of people with autism and their families for research. A study this large could lead to more scientific discoveries about autism, SPARK researchers said.

That’s how it started. So how is it going?

1. SPARK is the largest study of autism, ever

As of 2026, SPARK has 425,000 participants: 141,500 autistic children, 37,700 autistic adults, and their parents and siblings. The study has sequenced the DNA of more than 78,000 people with autism and 119,000 of their family members who contributed saliva for research.

2. Scientists using SPARK data have published more than 250 research papers

Researchers from around the world have used data from SPARK participants to expand what we know about autism, from its biology to the therapy and health needs of autistic people from early childhood to old age.

3. SPARK data helped identify more than 200 autism-related genes

SPARK participants helped scientists discover genes and chromosomes that contribute to autism and developmental conditions. Variations in many of these genes greatly increase the chances of having autism. Researchers also used SPARK data to identify some genes that, when altered, raise a person’s chances of having autism only moderately.

4. SPARK notified more than 4,000 participants that it found a genetic cause of their autism

SPARK notified more than 4,000 people that it had found a variation in their DNA that contributed to their autism. It’s a participant’s choice to be told their genetic results.

5. SPARK data has led to more understanding of the biology of autism

“One of the big things that SPARK has done is accelerate our understanding of the genetic contributions to autism,” said Wendy Chung, M.D., Ph.D., SPARK’s principal investigator, in a 2026 webinar.

Using SPARK data, scientists have:

• identified medical and physical features that help predict which autistic people likely have a rare genetic variant. These features include motor delays, large or small head sizes, and learning disabilities, among others.
• proposed four types of autism with different patterns of traits, along with genetic variants that are active at different stages of development.
• examined why girls and women are less susceptible than boys and men to genetic variants that raise the chances of having autism.
• explored the effects of the sex chromosomes (X and Y) on autism.

6. SPARK helped researchers find 74,500 participants for their studies

SPARK’s Research Match program has helped several hundred scientists find people for 350 studies on various topics. More than 157,500 parents and autistic adults have been invited to join these studies. Almost half have agreed.

Suppose a researcher wants to know what traits parents noticed in their children when they first suspected they were developing differently from others. SPARK makes it easier to find hundreds or thousands of parents who can answer that question. “And that scale provides really powerful answers to all of these questions that come up,” says professor Paul Carbone, M.D., a University of Utah researcher who works with SPARK.

7. SPARK participants are helping us learn more about autism in adulthood

For decades, autism research focused mostly on children. SPARK has made it easier for researchers to recruit adults into studies. More than 60 studies about adults have been published. Topics include mental and physical health, strengths, being LGBTQ+, stress, and quality of life. Studies have examined movement problems, parkinsonism symptoms, and cognitive decline in older adults.

8. SPARK made it easier to study autistic girls and women

Several decades ago, researchers struggled to find enough girls and women to study whether autism affects them differently than it affects boys and men. SPARK helped change that by registering 55,500 autistic girls and women. Studies on autistic girls and women found that:

• women reported more problems with their physical and mental health than men.
• girls have some different special interests, a trait of autism, and are more likely to hide their autism traits as teenagers, compared with boys.
• girls have different early delays in development, and are more likely to have anxiety, than boys.
• women diagnosed with autism in adulthood reported more anxiety, depression, eating disorders, and substance use disorders than women diagnosed as children.

9. SPARK families contributed to research on autism in people of different races and ethnicities in the U.S.

Autism affects people of all races, cultures, and ethnicities equally. But children of color have traditionally been diagnosed with autism later and received fewer autism services than average. Many groups also have been underrepresented in research. SPARK participants have contributed to studies that examined:

• the role that negative beliefs, called stigma, play in the use of autism services by people of different races and ethnicities.
• delays in diagnosis and barriers to treatment for Black families.
• the experiences of Black and multiracial families seeking an autism diagnosis and interventions.

10. SPARK data helped increase what we know about severe and profound autism

Fewer studies have focused on youth and adults who do not speak or have intellectual disability than on autistic people who speak or have average-range IQ. SPARK data is being used to:

• help identify depression in autistic adults with little or no speech.
• explore the link between positive social experiences and mental health in autistic youth with low IQ.
• identify rare gene variants that can contribute to severe autism.

Studying Autism Over Time

A long term study like SPARK allows researchers to study people over time. “Some people who have been involved in some of our studies … may report that something has changed for the better in their child with autism or, if they’re autistic themselves, in their own life,” says professor Jacob Michaelson, Ph.D., a University of Iowa researcher who works with SPARK.

“And that information is just like gold because we not only want to understand how things might get worse over time, but we definitely want to understand how and why things might get better. Because then we might be able to share that with others, so that other people can benefit from that same knowledge that that person did,” Michaelson says.

SPARK project director Amy Daniels, Ph.D., credits participants for pushing research forward. “It is so satisfying to witness all of the research that has been done and the discoveries that have been made in the last 10 years, thanks to the individuals and families that have entrusted us with their data and stories.”

Interested in joining SPARK? Here’s what you should know.

Photo credit: Bootstrap

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