For each splicing event, Genome-wide Complex Trait Analysis (GCTA) [30] was used to estimate heritability (h2) of the PSI (Ψ), i.e., proportion of variance in Ψ explained by all the genetic variants genome-wide. The GCTA-GREML approach was performed with Ψ as the molecular trait and using all genetic variants in the CMC samples having a genotype imputation score ≥0.6 and MAF ≥ 0.01. The estimation of h2 was adjusted for the covariates sex and sequencing cohort.
