Under enrollment of participants in clinical research is costly and delays study completion to impact public health. Given that research personnel make decisions about which strategies to pursue and participants are the recipients of these efforts, we surveyed research staff (n = 52) and participants (n = 4,144) affiliated with SPARK (Simons Foundation Powering Autism for Knowledge) – the largest study of autism in the U.S. – to understand their perceptions of effective recruitment strategies.

In Study 1, research personnel were asked to report recruitment strategies that they tried for SPARK and to indicate which ones they would and would not repeat/recommend. In Study 2, SPARK participants were asked to indicate all the ways they heard about the study prior to enrollment and which one was most influential in their decisions to enroll.

Staff rated speaking with a SPARK-study-team member (36.5%), speaking with a medical provider (19.2%), word of mouth (11.5%), and a live TV news story (11.5%) as the most successful strategies. Participants most often heard about SPARK via social media (47.0%), speaking with a medical provider (23.1%), and an online search (20.1%). Research personnel’s and participants’ views on effective recruitment strategies often differed, with the exception of speaking with a medical provider.

Results suggest that a combination of strategies is likely to be most effective in reaching diverse audiences. Findings have implications for the selection of strategies that meet a study’s specific needs, as well as recruitment-strategy “combinations” that may enhance the influence of outreach efforts.

SPARK launched in 2016 to build a US cohort of autistic individuals and their family members. Enrollment includes online consent to share data and optional consent to provide saliva for genomic analysis. SPARK’s recruitment strategies include social media and support of a nation-wide network of clinical sites. This study evaluates SPARK’s recruitment strategies to enroll a core study population.

Individuals who joined between January 31, 2018, and May 29, 2019 were included in the analysis. Data include sociodemographic characteristics, clinical site referral, the website URL used to join, how the participant heard about SPARK, enrollment completion (online registration, study consents, and returning saliva sample), and completion of the baseline questionnaire. Logistic regressions were performed to evaluate the odds of core participant status (completing enrollment and baseline questionnaire) by recruitment strategy.

In total, 31,715 individuals joined during the study period, including 40% through a clinical site. Overall, 88% completed online registration, 46% returned saliva, and 38% were core participants. Those referred by a clinical site were almost twice as likely to be core participants. Those who directly visited the SPARK website or performed a Google search were more likely to be core participants than those who joined through social media.

Being a core participant may be associated with the “personal” connection and support provided by a clinical site and/or site staff, as well as greater motivation to seek research opportunities. Findings from this study underscore the value of adopting a multimodal recruitment approach that combines social media and a physical presence.

Heterotaxy syndrome is caused by left–right asymmetry disturbances and is associated with abnormal lateralisation of the abdominal and thoracic organs. The heart is frequently involved and the severity of the abnormality usually determines the outcome.

We performed a direct sequence analysis of the coding sequence of genes including Zinc Finger Protein of the Cerebellum 3, Left–Right Determination Factor 2, Activin A Receptor Type IIB, and Cryptic in 47 patients with laterality defects and congenital cardiac disease.

Of the 47 patients, 31 (66%) had atrioventricular septal defects, 34 (72%) had abnormal systemic venous return, 25 (53%) had transposed or malposed great arteries, and 20 (43%) had pulmonary venous abnormalities. We identified two novel genetic changes in Zinc Finger Protein of the Cerebellum 3, and these variants were not present in 100 ethnically matched control samples. One previously reported missense mutation in Activin A Receptor Type IIB was identified in two unrelated subjects. The genetic changes identified in this study are all located in conserved regions and are predicted to affect protein function in left–right axis formation and cardiovascular development.

Mutations in Zinc Finger Protein of the Cerebellum 3 and Activin A Receptor Type IIB were identified in 4 of the 47 patients with heterotaxy syndrome for a yield of approximately 8.5%. Our results expand the mutation spectrum of monogenic heterotaxy syndrome with associated cardiac anomalies and suggest that there are other causes of heterotaxy yet to be identified.

Hypertrophic cardiomyopathy is the most common cause of sudden death in young people, including trained athletes, and is caused by mutations in genes encoding proteins of the cardiac sarcomere. Mutations in the Troponin C gene (TNNC1) are a rare genetic cause of hypertrophic cardiomyopathy. We describe a novel type of mutation (c.363dupG) in Troponin C, a rare form of hypertrophic cardiomyopathy.

A family in which a 19-year-old asymptomatic male died of sudden cardiac death due to hypertrophic cardiomyopathy was genetically studied by sequencing 17 genes associated with hypertrophic cardiomyopathy or its phenocopies.

A c.363dupG mutation in Troponin C was identified, and tested across the family.

We report the first frameshift mutation (c.363dupG or p.Gln122AlafsX30) in Troponin C causing hypertrophic cardiomyopathy (and sudden cardiac death) in a 19-year-old male, and have demonstrated that the mutation segregates with hypertrophic cardiomyopathy within the family.