TP53 and atrial fibrillation: The number of TP53 mutations was significantly higher in whole-skin TSC-FAF (median 5) than in TSC-NS (median 2) and TSC-UF/TSC-nipple AF (median 0) samples (Kruskal-Wallis test, P = 0.02), owing to expected differences in UV exposure in these biopsy sites (Figure 5B).