X linkage ofAP3A and Y linkage of AP3Yin both species indicates that the genes' ancestral progenitor resided on the autosomes that gave rise to the sex chromosomesand that neither gene has moved between chromosomes since species divergence.Consequently, our results do not support the contention that inter-chromosomal gene transfer occurred in the evolution of SlAP3Y from SlAP3A.
We considered only ortholog pairs that had moved between chromosomes, though without a further outgroup, we cannot polarize the direction of movement.
Interestingly, when each avian lineage was examined individually since their divergence, there were no retrogenes moving between chromosomes identified in the chicken, and only two identified in the zebra finch.
Our requirement that each block be fully contained with a chromosome may require that some evolutionary events, such as translocation, fusion and fission, all of which can move genomic material between chromosomes, be treated as block-splitting events.
They can move between genetic elements such as chromosomes, plasmids, and viruses, and across species boundaries (Chandler and Mahillon 2002; Siguier, Filee, et al. 2006).
Our results suggest that a common salmonid sex-determining gene (sdY) can move between three specific loci on chromosomes 2, 3, and 6, giving the impression that there are multiple SEX loci both within and between salmonid species.
The Philadelphia chromosome results from a gene exchange between chromosomes 9 and 22.
Chromosome conformation capture (3C) provides a powerful tool for detecting interactions within and between chromosomes.
The differences between the genders are more definite than the differences between the races from a strictly biological standpoint; consider, the differences between chromosomes and organs both internal and external.
Clustering can occur between chromosomes or within chromosomes.
