Rare-variant and polygenic analyses of amyotrophic lateral sclerosis in the French-Canadian genome.

PURPOSE: The genetic etiology of amyotrophic lateral sclerosis (ALS) includes few rare, large-effect variants and potentially many common, small-effect variants per case. The genetic risk liability for ALS might require a threshold comprised of a certain amount of variants. Here, we tested the degree to which risk for ALS was affected by rare variants in ALS genes, polygenic risk score, or both. METHODS: 335 ALS cases and 356 controls from Québec, Canada were concurrently tested by microarray genotyping and targeted sequencing of ALS genes known at the time of study inception. ALS genome-wide association studies summary statistics were used to estimate an ALS polygenic risk score (PRS). Cases and controls were subdivided into rare-variant heterozygotes and non-heterozygotes. RESULTS: Risk for ALS was significantly associated with PRS and rare variants independently in a logistic regression model. Although ALS PRS predicted a small amount of ALS risk overall, the effect was most pronounced between ALS cases and controls that were not heterozygous for a rare variant in the ALS genes surveyed. CONCLUSION: Both PRS and rare variants in ALS genes impact risk for ALS. PRS for ALS is most informative when rare variants are not observed in ALS genes.

Determining the minimally clinically important difference for the pediatric liver transplant quality of life questionnaire.

PURPOSE: The Pediatric Liver Transplant Quality of Life (PeLTQL) questionnaire is a disease-specific patient reported outcome measure for pediatric liver transplant (LT) recipients. To-date, threshold values above which a change in PeLTQL score is considered meaningful to patients are unavailable. This study proposes the first values for the minimally clinically important difference (MCID) for the PeLTQL. METHODS: In this retrospective cohort study, anchor and distribution-based methods were used to estimate the MCID for the PeLTQL. Questionnaires completed between March 2013, and July 2022 were included if data from two sequential visits were available. An internal anchor question was used for anchor-based determination of the MCID. A final MCID estimate was ascertained from triangulation of all methods. RESULTS: PeLTQL data from 65 LT recipients (26 [40%] male, 17 [42%] biliary atresia, median age at LT 3.08 years [interquartile range 0.99-7.30]), and their caregivers were included for analysis. Median patient age at time of baseline PeLTQL completion was 13.84 (10.90-15.86) years. The MCID for self-PeLTQL total scores ranged from 4.53 to 8.46, and from 4.47 to 8.85 for proxy responses. By triangulation, the MCID of the PeLTQL total score was 6.45 and 6.78 for self and proxy responses respectively. CONCLUSION: A change in PeLTQL score of 6.5 or more points suggests a change in health status that is meaningful to the patient, providing the clinical team an opportunity to engage the patient's voice in reassessing current health status and management strategies.