highly significantP < 0.001
The model shows a highly significant effect of both GENE (likelihood-ratio test: χ 2 = 487.495, 4 d.f., P < 0.001) and SITE (likelihood-ratio test: χ 2 = 634.952, 20 d.f., P < 0.001), which supports the hypothesis that the effect of mutations depends on the gene where they appear and that differences among individual mutations affecting the same gene also exist.