Quantitative analysis of two-dimensional gel electrophoresis protein patterns: a method for studying genetic relationships among Globodera pallida populations.

A method based in two-dimensional protein gel electrophoresis has been developed in order to improve the analysis of genetic relationships among populations of Globodera. It has been used to estimate genetic divergence among nine Globodera pallida nematode populations. Sixty-one anonymous polypeptide spots were resolved using silver-stained high-resolution 2D gels and they were quantified in each population to establish genetic variation among G. pallida populations. The results of this analysis were compared with those obtained after a study of allelic frequency variation, which was carried out using seven previously described loci. Genetic distances among populations were calculated by means of both studies, the quantitative analysis and the allelic frequency variation, and phylogenetic trees were constructed for each type of analysis. A correlation analysis between the two distance matrices was carried out and a bootstrap analysis was performed to determine the strength of the clusters obtained with each method. The results obtained support the idea that quantitative protein analysis can be successfully applied to phylogenetic analysis of G. pallida populations.