For most organisms, crossovers forming during meiosis exhibit crossover interference – nearby crossovers are rare. This phenomenon was studied in great detail in Arabidopsis thaliana using a large backcross population for male and female meiosis. We used the gamma two-pathway model by superposing proportion (1- p) of interfering crossovers with p of non-interfering crossovers. It was observed that female meiosis shows higher interference but lower proportion of non-interfering crossovers than male meiosis. Further intra-chromosomal interference comparisons conclude that there are variations between (a) left and right arms, and (b) the central versus distal regions of a chromosome. Then statistical tests revealed heterogeneities in the non-interfering crossover proportion along chromosomes. Thereafter various statistical tools developed to examine a very novel wild-type tomato data annotating crossover positions from both pathways provided evidence for ‘cross-talk’ between the two pathways of crossover formation as opposed to being independent. Finally a model named Pathway-Specific Landscapes Gamma-Sprinkling (PSL-GS) incorporating chromosomal non-uniformity in the individual pathways has been proposed to extend present state-of-the-art interference modeling which consider both pathways to be uniform along chromosomes.
