About this Research Topic
Composite breeds are widely used in livestock, aiming to combine high production and environmental adaptability. Brangus cattle, for example, combine high yield and meat quality of Angus with tropical adaptation of Brahman. After initial crossbreeding, these breeds are maintained as purebred animals, retaining some heterosis in future generations without crossbreeding. Thereafter, composite breeds are one of the ways to exploit heterosis and maintain replacement females from within the herd. Simultaneously, composite breeds represent a unique opportunity to understand how heterosis and selection interplays in a genomic perspective.
Selection signatures are normally identified as genomic regions with low diversity and/or homozygosity. Generally, “old” selection signatures (tracing back for several generations) are easier to be identified than “new” selection signatures (coming from selection in the last 3 to 5 generations). Therefore, the identification and characterization of selection signatures in composite breeds can be challenging.
Selection signatures in composite breeds with recent crossbreeding is a challenging topic, therefore several questions remain. Are the regions identified as selection signals truly related to any selection or only artifacts due the crossbreeding process? How many generations after the initial crossbreeding are required to be able to identify genomic selection signatures? This Research Topic intends to provide a forum about genetic diversity and selection signatures in composite breeds, aiming to provide some answers to these questions. The comprehension of how selection signatures, genomic breed composition and heterosis interplays in composite breeds can provide a glimpse on better ways to form new composite breeds or improve selection in the current ones.
We welcome both Review and Original Research articles that contribute to enhancing the genomic understanding of formation and stabilization of breed composition with the arising of selection signatures in composite breeds. Potential topics include, but are not limited to, the following:
· Selection signatures according to generation after the initial crossbreeding.
· Identification of runs of homozygosity in composite breeds and their relationships with the generations inside the breed.
· Identification of selection signatures with different methodologies in composite breeds
· Genomic breed composition (GBC) in composite breeds, considering a genome-wide perspective and also specific genomic regions and the relationship of these results with generations and phenotypes of interest.
· Genetic diversity of composite breeds and the relationship with geographic patterns.
· Genomic heterosis effect in traits and phenotypes of interest in crossbred and composite cattle.
· Studies dealing with phenotypic and genomic data in composite breeds.
Selection signatures are normally identified as genomic regions with low diversity and/or homozygosity. Generally, “old” selection signatures (tracing back for several generations) are easier to be identified than “new” selection signatures (coming from selection in the last 3 to 5 generations). Therefore, the identification and characterization of selection signatures in composite breeds can be challenging.
Selection signatures in composite breeds with recent crossbreeding is a challenging topic, therefore several questions remain. Are the regions identified as selection signals truly related to any selection or only artifacts due the crossbreeding process? How many generations after the initial crossbreeding are required to be able to identify genomic selection signatures? This Research Topic intends to provide a forum about genetic diversity and selection signatures in composite breeds, aiming to provide some answers to these questions. The comprehension of how selection signatures, genomic breed composition and heterosis interplays in composite breeds can provide a glimpse on better ways to form new composite breeds or improve selection in the current ones.
We welcome both Review and Original Research articles that contribute to enhancing the genomic understanding of formation and stabilization of breed composition with the arising of selection signatures in composite breeds. Potential topics include, but are not limited to, the following:
· Selection signatures according to generation after the initial crossbreeding.
· Identification of runs of homozygosity in composite breeds and their relationships with the generations inside the breed.
· Identification of selection signatures with different methodologies in composite breeds
· Genomic breed composition (GBC) in composite breeds, considering a genome-wide perspective and also specific genomic regions and the relationship of these results with generations and phenotypes of interest.
· Genetic diversity of composite breeds and the relationship with geographic patterns.
· Genomic heterosis effect in traits and phenotypes of interest in crossbred and composite cattle.
· Studies dealing with phenotypic and genomic data in composite breeds.
Keywords: crossbred, genomics, farm animals, genetic resources, livestock
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.
