CLK2 and pachyonychia congenita: Moreover, Kaplan–Meier plots for disease‐free survival using data from the TCGA database [20] containing early stage PC demonstrated significantly decreased survival rates for high CLK2 (Fig. 4D left) and high SRSF9 (Fig. 4D, right) expression when the cohorts were chosen to contain the bottom and top quarter of the quantified CLK2 or SRSF9 reads, respectively.