Abstract
Balanced chromosome rearrangements are one of the main etiological factors contributing to hypoprolificacy in the domestic pig. Amongst domestic animals, the pig is considered to have the highest prevalence of chromosome rearrangements. To date over 200 unique chromosome rearrangements have been identified. The factors predisposing pigs to chromosome rearrangements, however, remain poorly understood. Nevertheless, here we provide empirical evidence which sustains the notion that there is a non-random distribution of chromosomal rearrangement breakpoints in the pig genome. We sought to establish if there are structural chromosome factors near which rearrangement breakpoints preferentially occur. The distribution of rearrangement breakpoints was analyzed across three level, chromosomes, chromosome arms, and cytogenetic GTG-bands (G-banding using trypsin and giemsa). The frequency of illegitimate exchanges (e.g., reciprocal translocations) between individual chromosomes and chromosome arms appeared to be independent of chromosome length and centromere position. Meanwhile chromosome breakpoints were overrepresented on some specific G-bands, defining chromosome hotspots for ectopic exchanges. Cytogenetic band level factors, such as the length of bands, chromatin density, and presence of fragile sites, were associated with the presence of translocation breakpoints. The characteristics of these bands were largely similar to that of hotspots in the human genome. Therefore, those hotspots are proposed as a starting point for future molecular analyses into the genomic landscape of porcine chromosome rearrangements.
Highlights
Chromosome rearrangements are known to be one of the main etiological factors contributing to hypoprolificacy in domestic species, especially the domestic pig [1,2,3]
We considered whether the relative position of a cytogenetic band on chromosome arms affected its translocation frequency
Observing the distribution of translocation breakpoints across chromosomes, chromosome arms, and cytogenetic bands revealed the chromosome regions most susceptible to rearrangement, and physical features that are associated with higher breakpoint number and translocation frequency
Summary
Chromosome rearrangements are known to be one of the main etiological factors contributing to hypoprolificacy in domestic species, especially the domestic pig [1,2,3]. To date over 200 distinct chromosome rearrangements have been identified in the domestic pig. The vast majority are balanced reciprocal translocations, making up over 90% of described rearrangements [4]. It is estimated that chromosome rearrangements in domestic pigs occur spontaneously in one of 200 live births [5,6]. The prevalence of chromosome rearrangements among swine herds is thought to be between 0.5% and. Reciprocal translocations are quite prevalent throughout swine herds and the genetic and genomic reasons for this are poorly understood
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
