Fig. 2.

Principal components analysis (PCA) from a genome-wide association study reported by the GenoMEL consortium (2). The coloured dots represent a measure of the genetic inheritance of participants in a genetic study of melanoma. The superimposed blue, green and terracotta dots over the UK suggests that the participants from two sites in Australia (Sydney and Brisbane) were very similar genetically to those living in the UK. This was expected as many Australian melanoma patients report ethnicity as the UK. Comparing incidence in melanoma then between the UK and Australia is to some degree comparing incidence in two populations similar genetically but with very different sun exposure histories. Figure kindly prepared by Dr Mark Iles of the University of Leeds.