Functional Abilities In TUBB4A-Related Disorders: An Exploratory Study Of Motor Performance And Parent Reported Outcomes

Abstract

<h3>Research Objectives</h3> -To characterize the performance of the TUBB4A-related disorder population at traditional gross motor evaluations and adaptive behavior questionnaires. -To determine the functional performance of the population and confirm the existence of a functional genotype/phenotype correlation. <h3>Design</h3> Prospective study. <h3>Setting</h3> Children were evaluated by providers trained in the administration of Gross Motor Function Measure-88 (GMFM-88), and Vineland Adaptive Behavior Scale 3rd edition (VABS-3) Parent/Caregiver Form. Motor function and adaptive behavior abilities were assessed with hybrid in-person/remote evaluations, due to COVID-19 pandemic constrains in travel. <h3>Participants</h3> Fifty individuals with a clinical and molecular diagnosis of TUBB4A-related disorders. <h3>Interventions</h3> None. <h3>Main Outcome Measures</h3> GMFM-88, VABS-3. <h3>Results</h3> Patients showed severe gross motor impairment, with floor effect performance at the GMFM-88. Impaired performance of motor abilities and daily living skills was observed at the VABS-3, while social and communicative abilities were relatively spared. A genotype-phenotype correlation was observed, with a lower overall functional level observed in the non-p.Asp249Asn subcohort. <h3>Conclusions</h3> The severe motor impairment observed in this population makes challenging the administration of commonly administered gross motor assessments such as the GMFM-88, while the VABS-3 appears to describe better this population, being able to highlight functional differences associated with specific genotypes. The identification of outcome measures tailored on populations with rare disorders has the potential to be helpful in clinical prognostication as well as cohort selection for future clinical trials. <h3>Author(s) Disclosures</h3> None.