I am an associate professor working principally with quantitative traits, with an overall aim to identify and characterise how these small-effect loci can modify the overall phenotype. My lab uses a variety of different techniques, principally involving a variety of QUantitative Trait Loci (QTL) mapping and expression QTL mapping. I have worked with both zebrafish and chickens, and in both these study systems have used domesticated (or in the case of zebrafish, laboratory) strains crossed with wild-derived animals in order to identify the genetic components that separate these populations. These genetic loci can then be used to address a series of different question, outlined in brief below. More recently, I have become, in collaboration with Dr. Eben Gering, interested in the genetic responses to feralisation. Feralisation, the process whereby domestic animals are released into the wild, represents an excellent opportunity to study domestication 'in reverse' and to identify loci affected by natural and sexual selection from a different perspective.
Genetics of sexual ornaments, fecundity and bone allocation
As well as studying sexual ornaments for size, other aspects (including colour and morphology) can be analysed using QTL and eQTL methods. In addition, classic mutations affecting the comb (pea comb mutation, rose comb mutation, etc) can also be mapped, with the possibility of mutation identification far greater in these cases. By identifying such mutations and the genes that they affect, the architecture of these traits can be looked at in greater detail than is often possible with conventional QTL analysis, whilst over-lapping regions between such mutation and QTL analyses can also aid in the discovery of quantitative trait nucleotides (QTNs). To date we have used this method to identify that the genes HAO1 and BMP2 appear to modify comb size in the domestic chicken, with these genes also having potentially pleiotropic effects on fecundity traits. We have subsequently expanded the number of candidates for this sexual ornament using genome-wide eQTL scans to identify five more loci. By studying the comb, which is primarily based on collagen deposits, my lab has now also become interested in the genetics of bone allocation. Comb mass reflects bone allocation and egg production in chickens, and many of the loci affecting comb mass, also appear to be either linked or pleiotropic with loci affecting bone allocation or fecundity.
Johnsson et al. 2014. The role of pleiotropy and linkage in genes affecting a sexual ornament and bone allocation in the chicken. Molecular Ecology 23 (9). 2275-2286
Johnsson et al. 2012. A sexual ornament is affected by pleiotropic alleles at HAO1 and BMP2, selected during domestication. PloS Genetics. 8. e1002914.
Wright et al. 2009. Copy number variation in intron 1 of SOX5 causes the pea comb phenotype in chickens. PLoS Genetics. 5. e1000512
Wright et al. 2008. the genetic architecture of a female sexual ornament. Evolution. 62: 86-98
Genetics of feralisation
Chickens have long been present on the island of Kauai in Hawaii, with Red Junglefowl birds originally brought over by colonists in 1200AD. Subsequently, re-introductions have also occurred. During hurricanes Ewa and Iniki in 1982 and 1992, large numbers of domestic birds were released and subsequently hybridised with the RJF reservoir population. In collaboration with Dr. Eben Gering, my lab has been looking at the genetic changes that act on the genome during this feralisation process.
Gering et al. 2015. Mixed Ancestry and admixture in Kauai's feral chickens: invasion of domestic genes into ancient Red Junglefowl reservoirs. Molecular Ecology (advanced online early).
Genetics of behaviour
I am interested in the role of genetics in determining behavioural response in a variety of evolutionarily relevant behaviours, though principally anxiety-related. Using QTL and eQTL studies in combination with wild and domestic populations it is possible to take advantage of the large selective differences to indicate genetic regions of interest in these traits and to more finely genetically dissect these characteristics. Using this technique, we have identified a number of candidate causal genes for anxiety.
Genetics of domestication
Domestication has been central to the advent of modern civilization, yet the underlying genetics still remain opaque. Most importantly, despite similar changes seen in numerous species, it is not clear if these are acting pleiotropically, or whether the changes are driven by linkage ‘modules’. We have shown to date that domestication appears to have favoured 'modules', with each module consisting of multiple loci that influence only one or two traits, though potentially surrounding more pleiotropic loci.
Wright et al. 2010. The genetic architecture of domestication in the chicken: effects of pleiotropy and linkage. Molecular Ecology 19: 5140-5156
Name: Dominic Wright
Title: Assistant Professor
Department: IFM Biology
Ph: +46 13 28--
Fax: +46 13 ---
Department of Physics, Biology and Chemistry,
Division of Zoology, AVIAN Behavioural Genomics and Physiology Group
S – 581 83 Linköping
Last updated: Sun Apr 05 12:03:17 CEST 2015