I find this fascinating to think about. It seems obvious that there would be genetic differences and differences in neural-organisation between left-wing people and right-wing people. They have different priorities and different values. (Obviously experiences, teachers, books, have a role too.)

ALFORD, J. R., FUNK, C. L., & HIBBING, J. R. (2005). Are Political Orientations Genetically Transmitted? American Political Science Review, 99(02), 153–167. doi:10.1017/s0003055405051579 found that monozygotic twins have closer political beliefs than dizygotic ones.

Hatemi, P. K., Gillespie, N. A., Eaves, L. J., Maher, B. S., Webb, B. T., Heath, A. C., … Martin, N. G. (2011). A Genome-Wide Analysis of Liberal and Conservative Political Attitudes. The Journal of Politics, 73(1), 271–285. doi:10.1017/s0022381610001015 found a bunch of genes that correlate with political orientation

Eaves, L., Heath, A., Martin, N., Maes, H., Neale, M., Kendler, K., … Corey, L. (1999). Comparing the biological and cultural inheritance of personality and social attitudes in the Virginia 30 000 study of twins and their relatives. Twin Research, 2(02), 62–80. doi:10.1375/twin.2.2.62 also points to some specific genes.

It's just fascinating thinking about how people are walking around with these genes in their cells that are pushing them to take part in the competing forces within a society.