Often when we see what is going on in terms of genetics in other fields we utter the words "if only..." as in "if only we would do this in thoroughbreds....".
I woke up this morning to read an interesting paper in Nature Genetics. The paper was on the prediction of complex traits in maize but it was an interesting paper in that it combined the use of baseline DNA (genomics) and metabolomics to derive its prediction model. It was very interesting to see how the researchers used what was inherited (genomic DNA) and following transcription and protein creation, how it interacted with the environment (metabolomics) to come up with a prediction model for complex traits. For those that aren't as up to date as others, genomics, or baseline DNA, goes through a process of transcription, where gene-gene interactions take place that may influence the outcome and then the creation of proteins, where more gene-gene interactions take place and gene-environment interactions take place, to end up with the end products of the cellular processes, known as metabolites (the study of which is metabolomics).
Metabolomics is where the 'rubber meets the road' in terms of genetics in that the metabolites running around in your body, and that of the thoroughbred, are the result of inherited genetics and environment (a good example here is a horse can have great DNA but if he got sick as a foal and it compromised its immune system it may never be the horse it could have been). To date, while there has been some studies in thoroughbreds at the transcription and proteomic level, the bulk of the genetic study on thoroughbreds has been done at a genomic level, so the interaction of environment and gene-gene interactions can't be considered. It is one of the challenges that we ourselves have in creating our prediction model and is why we don't solely rely on genomic data to make our assessment of potential. While genomics gives us a significant edge in identifying this talent, there is just too much that can occur with unknown gene-gene interactions and gene-environment interactions that can 'muddy the waters', so to speak. We discussed in an earlier post how technology will soon make full genome studies a reality in human genomes, and probably shortly thereafter horse genomes. There has also been some work done on metabolic profiles in humans after exercise which is really interesting and one has to think that in the next few years time, when both technologies have matured a little more (metabolomics is still very much an emerging field), we will be able to do both of these processes in thoroughbreds and in doing so have a much more comprehensive prediction model of performance and just as importantly, a greater understanding of breeding outcomes to breed that elusive champion.