Mapping Unequal Crossing over Hotspot Region of Simple Sequence Repeat in Maize

The polymorphism of simple sequence repeat(SSR) in biological genome is one result of unequal crossing over for homologous chromosomes;therefore it has theoretical importance in clarifying the hotspot regions of unequal crossing over.A set of recombinant inbred lines(RILs) population that derived form an elite hybrid Yuyu 22 was used in this study,its genetic components of the population was analyzed by means of SSR analysis,and 40 unequal crossing over SSR markers were found.The frequency of the unequal crossing over in the RIL population was 0.34-14.63%,with 10-2-10-1 frequency per generation,and the(AG)n repeat SSR markers accounted for 58.3%.There were 31 unequal crossing over markers locating on 11 chromosomal hotspot regions,distributing on 10 chromosomes except for chromosome 9,including two unequal crossing over hotspot regions each in chromosomes 3 and 5.