Individuals with autism spectrum disorder (ASD) demonstrate a diverse array of clinical features, complicating efforts to both understand the causes of the condition and develop treatments. Launched in 2016, SPARK (Simons Foundation Powering Autism Research for Knowledge) is a program of the Simons Foundation Autism Research Initiative (SFARI) that aims to build and retain a cohort of 50,000 families with autism— the largest autism cohort in the world— to advance research on the genetic, behavioral and clinical features associated with the condition¹.

“If we want to understand the causes of autism, and ultimately get to effective treatments and supports for more individuals, researchers need data collected from large numbers of individuals who they can connect with over years of study,” says SPARK scientific director Pamela Feliciano.

SPARK now collaborates with 31 university-affiliated clinical sites and several national and local autism organizations across the United States (Figure 1). Through these recruitment sites and other marketing efforts, SPARK has enrolled over 280,000 individuals, including over 100,000 children and adults with ASD. In conjunction with the clinical sites and other partners, SPARK is working to reach its goal of recruiting and sequencing 50,000 autism families, which will be necessary to identify most genetic mutations that may confer risk for ASD.

SPARK families are diverse, spanning a broad range of geographic communities and sociodemographic characteristics. Broad outreach and an accessible, online registration process have helped the study grow in its diversity over time. SPARK also provides interested families with their behavioral and ASD genetic results, which in turn can empower families with better knowledge of their autism.

“We are so grateful to our participating families,” says Wendy Chung, SPARK’s principal investigator and director of clinical research at SFARI. “Knowledge is power, and by working together with scientists, SPARK participants are providing new insights into the causes of ASD that can lead to new treatments and supports.”

The information provided by SPARK participants is a goldmine of data for researchers. Detailed phenotypic data are now available for 269,139 SPARK participants, including extensive medical and developmental histories collected through behavioral questionnaires and medical records. Genetic data are also being collected through saliva samples contributed by the study participants and currently available for over 69,000 participants, including exomes and genomes from more than 33,000 individuals with ASD.

All SPARK data, including both genetic and phenotypic information, are made available to approved researchers upon request through SFARI Base. Researchers can apply to use these data in studies that address a variety of clinical, behavioral and genetic questions relevant to ASD, as well as other research topics not limited to autism.

By engaging in long-term collaborations with SPARK participants, researchers gain a greater ability to explore the links between the complex genetic landscape and varied presentation of ASD. This bridge between SPARK families and researchers is being further aided by a research matching program launched in 2017, which connects SPARK families to a diverse set of research opportunities, including online surveys, brain imaging studies, genotype-phenotype analyses and clinical trials. To date, SPARK Research Match has launched more than 100 research studies addressing different questions about autism. A list of publications that use Research Match resources can be found here.

The collaboration between SPARK families and researchers has, over the past five years, enabled the publication of 39 published research studies and preprint articles. These studies have provided numerous insights into the genetic landscape of ASD, as well as the clinical and behavioral features of the condition. These findings will contribute to better understand the causes of the condition, its diverse manifestations and improve the interactions between families and their medical support systems.

As of 2021, more than 100 genes have been linked to autism ². SPARK genomic data have contributed to identify new candidate risk genes³ and have been used in several publications examining genetic risk factors in autism. SPARK also curates a list of genes and copy number variations (CNVs) that are known to be associated with autism. The list, which currently counts 157 genes and 19 CNVs, is updated quarterly as new findings emerge. SPARK participants who are found to have mutations in these genes are notified of their genetic diagnosis — a process that has been life changing for many families (Movie 1). To date, 500 SPARK participants have received a genetic result for their autism.

Other SPARK-supported studies have contributed to better understand the many challenges that people with autism may face. For example, one study demonstrated that children with ASD have motor impairments^4,5, yet only a small portion of these children receive physical therapy interventions⁴, suggesting that children diagnosed with ASD would benefit from motor evaluations and subsequent interventions as needed. Additional work has demonstrated that where families live — in urban versus more rural settings — affects both the types, and impacts, of behavioral and therapy-based ASD treatments⁶, which highlights the need for easily accessible ASD support programs in more rural settings.

Treatment studies often use caregiver questionnaires to assess the effectiveness of medications and interventions. One new caregiver questionnaire, called the Autism Impact Measure (AIM), was the focus of an early study using SPARK data⁷. That study found that caregiver reports on the AIM have clinical value and utility in real-world monitoring of ASD.

Studies with SPARK have also documented many of the underlying causes of childhood vaccination hesitancy in families with ASD^8–10. These findings are providing the medical community with information as to how best to address family concerns around childhood vaccinations.

During the COVID-19 pandemic, SPARK has been investigating how the pandemic is affecting individuals with ASD and their access to services. Thanks to many families who continue to demonstrate a willingness to get involved in new research studies, this research has highlighted a greater need for psychological supports during this unprecedented time¹¹, as well as significant, ongoing disruptions to effective therapy as a result of the pandemic¹².

“These findings have only been made possible because of the long-term commitment from our participating families,” says Feliciano. “SPARK is engaging and empowering families in our mission to understand and treat ASD, and their participation is helping to inform real-world clinical treatment plans for individuals with ASD.”

In addition to advancing research, the SPARK consortium helps create a community support system by connecting families who have the same genetic changes. Families provided with insights into their specific ASD genetic changes are also given the opportunity to join another SFARI-funded cohort — Simons Searchlight — an initiative that provides community to families and promotes research into rare neurodevelopmental conditions. This gives participants the opportunity to continue the journey of discovery they started with the SPARK study, while meeting families with similar challenges and life experiences, and creating contacts with the organizations that run periodic family meetings.

ASD is a genetically and phenotypically complex condition. While scientists have taken remarkable steps to find its causes and mechanisms, much remains to be discovered. SPARK was launched with the goal of transforming the way ASD research is done. Over the past five years, SPARK has helped accelerate discovery into the genetic causes of ASD, come over halfway to meeting the objective of recruiting, sequencing and retaining 50,000 diverse families with ASD, and helped accelerate genetic, behavioral and clinical research on many fronts. Ongoing efforts to recruit additional families and improve diversity, equality and inclusion in the study promise to open up avenues for an even greater understanding of, and treatments for, ASD.

The large scale of the project will make it possible to deconstruct the autism spectrum and make sense of the heterogeneity that, until now, has made it difficult to replicate studies and move forward. Novel technologies are likely to play a huge part in this, and SPARK is actively considering applications that will collect standardized multidimensional (e.g., behavioral, physiological) data from the real world.

As the genetics field is moving fast, SPARK aims to find answers. Ultimately, this means finding the genes and CNVs involved, as well as identifying the underlying biological mechanisms and potential targets for treatments.

“We are here for the long haul,” Chung says. “Our goal is to make the lives of individuals with autism and their families better, fuller, richer and easier.”

Anyone interested in learning more about SPARK can visit www.SPARKforAutism.org.

More information about the first five years of SPARK can be found here.

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