Expanding genotype-phenotype correlations in FOXG1 syndrome: results from a patient registry.

BACKGROUND: We refine the clinical spectrum of FOXG1 syndrome and expand genotype-phenotype correlations through evaluation of 122 individuals enrolled in an international patient registry. METHODS: The FOXG1 syndrome online patient registry allows for remote collection of caregiver-reported outcomes. Inclusion required documentation of a (likely) pathogenic variant in FOXG1. Caregivers were administered a questionnaire to evaluate clinical severity of core features of FOXG1 syndrome. Genotype-phenotype correlations were determined using nonparametric analyses. RESULTS: We studied 122 registry participants with FOXG1 syndrome, aged < 12 months to 24 years. Caregivers described delayed or absent developmental milestone attainment, seizures (61%), and movement disorders (58%). Participants harbouring a missense variant had a milder phenotype. Compared to individuals with gene deletions (0%) or nonsense variants (20%), missense variants were associated with more frequent attainment of sitting (73%). Further, individuals with missense variants (41%) achieved independent walking more frequently than those with gene deletions (0%) or frameshift variants (6%). Presence of epilepsy also varied by genotype and was significantly more common in those with gene deletions (81%) compared to missense variants (47%). Individuals with gene deletions were more likely to have higher seizure burden than other genotypes with 53% reporting daily seizures, even at best control. We also observed that truncations preserving the forkhead DNA binding domain were associated with better developmental outcomes. CONCLUSION: We refine the phenotypic spectrum of neurodevelopmental features associated with FOXG1 syndrome. We strengthen genotype-driven outcomes, where missense variants are associated with a milder clinical course.

"I wish that there was more info": characterizing the uncertainty experienced by carriers of pathogenic ATM and/or CHEK2 variants.

Little is known about what uncertainties patients experience after being identified to carry a pathogenic variant in a moderate-risk cancer gene as a result of undergoing multigene panel testing for cancer susceptibility. Data regarding cancer risk estimates and effectiveness of risk management strategies for these variants continues to evolve, which has the potential to evoke uncertainty. Acknowledging uncertainty during pre- and post-test discussions is imperative to helping individuals to adapt to their results. A better understanding of this population's experience of uncertainty is needed to facilitate such discussions and is the aim of the current study. Semi-structured interviews (30-60 min in length), informed by Han and colleagues' taxonomy of uncertainty in clinical genomic sequencing, were conducted to assess motivations to pursue genetic testing, areas of perceived uncertainty, and strategies for managing uncertainty among 20 carriers of pathogenic variants in two moderate-risk genes, ATM and CHEK2. We found that participants pursue genetic testing with the expectation that results will clarify cancer risks and approaches to management. Participants experience uncertainties aligning with Han's taxonomy relating to the ambiguity of specific cancer risk estimates and effectiveness of certain risk management strategies. These uncertainties influenced decisions around the uptake of risk management strategies, which were additionally impacted by clinicians' uncertainty towards such strategies. Participants employ a variety of uncertainty management approaches to cope with their anxieties. Clinicians may wish to use these findings to facilitate patient adaptation to the implications of multigene panel testing for cancer susceptibility during both pre- and post-test counseling sessions.