Cancer incidences in Europe related to mortalities, and ethnohistoric, genetic, and geographic distances

We have previously shown that geographic differences in cancer mortalities in Europe are related to tin order of importance): geographic distances (re flecting environmental differences), ethnohistoric distances (encompassing cultural and genetic attributes), and genetic distances of the populations in the areas studied. In this study, we analyzed the relations of the same three factors to European incidences of 45 male and 47 female cancers. Diff erences in cancer incidences are correlated moderately, first with geograph ic distances, and then with genetic distances, but not at all with ethnohis toric distances. Comparing these findings to the earlier ones for cancer mo rtalities, we note the reversal in the importance of ethnohistory and genet ics, and the generally lower correlations of incidence differences with the three putatively causal distance matrices. A path diagram combining both s tudies demonstrates the lack of cultural carcinogenic effects, but suggests cultural influences on procedures such as the registration of deaths in di fferent political entities. Additionally, the relatively large correlation between ethnohistoric distances and mortality differences is caused by comm on factors behind the correlation of ethnohistoric and geographic distances . Geographic proximity results in similar ethnohistories. The direct effect s of genetic distances are negligible and only their common effects with ge ographic distances play a role, accounting for the weak to negligible influ ence of genetics on incidence and mortality differences. Apparently, the ge netic systems available to us do not substantially affect cancer incidence or mortality. We present indirect evidence that international differences i n the quality of cancer rate data are greater in mortalities than in incide nces.