Significance The majority of eukaryotes reproduce sexually, creating genetic variation within populations. Sexual reproduction requires gamete production via meiotic cell division. During meiosis, homologous chromosomes pair and undergo exchange, called crossover. Crossover is vital for crop breeding and remains a major tool to combine useful traits. Despite the importance of crossovers for breeding, their levels are typically low, with one to two forming per chromosome, irrespective of physical chromosome size. Here we genetically engineer superrecombining Arabidopsis , via boosting the major procrossover pathway (using additional copies of the HEI10 E3-ligase gene), and simultaneously removing a major antirecombination pathway (using mutations in RECQ4A and RECQ4B helicase genes). This strategy has the potential to drive massive crossover elevations in crop genomes and accelerate breeding.
Serra et al. (Tue,) studied this question.