Evolutionary genomics model of chromosome number reduction and B chromosome production

In the long-term evolution, the number of chromosomes shows dynamic changes. There are still many mysteries about eukaryote chromosome evolution, one is how to maintain a small chromosome number, the other is how to produce B chromosome. The development of whole genome sequencing provides a new opportunity to understand chromosome number changes, especially after repeated polyploidy events. Through comparative genomics analysis, we propose an evolutionary model of chromosome number change and B chromosome production, and we propose that the reduction of chromosome number is mainly due to chromosome fusion, which shows that the loss of telomere and the formation of B chromosome play an important role in genome repatterning and chromosome number reduction.