Establishment and inheritance of minichromosomes from Arabidopsis haploid induction.

Minichromosomes are small, sometimes circular, rearranged chromosomes consisting of one centromere and short chromosomal arms formed by treatments that break DNA, including plant transformation. Minichromosomes have the potential to serve as vectors to quickly move valuable genes across a wide range of germplasm, including into adapted crop varieties. To realize this potential, minichromosomes must be reliably generated, easily manipulated, and stably inherited.

LD-CNV: rapid and simple discovery of chromosomal translocations using linkage disequilibrium between copy number variable loci.

Large-scale structural variations, such as chromosomal translocations, can have profound effects on fitness and phenotype, but are difficult to identify and characterize. Here, we describe a simple and effective method aimed at identifying translocations using only the dosage of sequence reads mapped on the reference genome. We binned reads on genomic segments sized according to sequencing coverage and identified instances when copy number segregated in populations.

Rare instances of haploid inducer DNA in potato dihaploids and ploidy-dependent genome instability.

In cultivated tetraploid potato (Solanum tuberosum), reduction to diploidy (dihaploidy) allows for hybridization to diploids and introgression breeding and may facilitate the production of inbreds. Pollination with haploid inducers (HIs) yields maternal dihaploids, as well as triploid and tetraploid hybrids. Dihaploids may result from parthenogenesis, entailing the development of embryos from unfertilized eggs, or genome elimination, entailing missegregation and the loss of paternal chromosomes.

Genomic Outcomes of Haploid Induction Crosses in Potato ( L.).

The challenges of breeding autotetraploid potato () have motivated the development of alternative breeding strategies. A common approach is to obtain uniparental dihaploids from a tetraploid of interest through pollination with Andigenum Group (formerly ) cultivars. The mechanism underlying haploid formation of these crosses is unclear, and questions regarding the frequency of paternal DNA transmission remain.