Genome sequence and assembly of abnormal chromosome 10 genome Ab10

Abnormal chromosome 10 (also known as K10) was identified by Longley (1937) and extensively characterized at the genetic level by Marcus Rhoades (see Birchler et al., 2003) and at the molecular level by Kelly Dawe and colleagues (Dawe et al., 2018). It is characterized by an extension of the long arm with three small knobs and one large knob. This novel region, the Ab10 haplotype, is bounded on the left by the R1 gene does not recombine with the end of normal chromosome 10. In lines carrying Ab10, knobs are transformed into motile neocentromeres that move poleward in meiosis. When crossed as a female, the Ab10 haplotype is preferentially transmitted to progeny in a process known as meiotic drive. A line carrying the Ab10 haplotype linked to R1 was obtained from Marcus Rhoades and crossed to B73 6 times and self crossed 5 times (BC6F5) to create the B73-Ab10 inbred. The inbred also contains the C1 gene from the original parent. The Ab10 genome has been sequenced and assembled by the NAM Sequencing Consortium using PacBio, Nanopore, and BioNano technology, and the resulting scaffolds ordered and oriented using linkage data.