Sunday, July 22, 2012

4th International Conference of Quantitative Genetics: Understanding Variation in Complex Traits

Last month the beautiful city of Edinburgh hosted the 4th International Conference on Quantitative Genetics. Over 600 delegates were registered to attend from over 50 countries (including several from Sweden), listening to talks by people working on complex traits in human health and disease, agriculture, natural populations and evolution.

Despite spending the week feeling intellectually inadequate, the conference was excellent and attended by many of the who’s who in quantitative genetics. The program was single session, meaning I saw a number of talks I wouldn’t have normally seen. There were several excellent talks, covering a wide range of different quantitative genetic approaches, including incorporating new molecular techniques such as GWAS. One minor complaint would be that several talks seemed to simply show variation in complex traits using (mind blowingly) huge sample sizes in GWAS studies, without any obvious underlying questions behind the research. However, this could simply be me missing the point, or not understanding different research approaches.

Several talks would have been of interest to some of the lab members in Lund.
Mark Blows, from UQ, gave a talk on “Evolution of genetic variance under selection” summarising his work over the past 10 years on natural populations of Drosophila serrata (the organism I'm currently working on). He talked about his work on multivariate constraints, showing that despite the presence of genetic variance in male sexual signalling traits, the direction of sexual selection on these traits is associated with low levels of genetic variance in multivariate space. Despite this, the genetic variance in these traits has been shown to evolve, with the limiting response of these traits seemingly resulting from pleiotropic associations between the sexually selected traits and other (unmeasured) traits under natural selection.

Jarrod Hadfield’s talk entitled “What, me natural? Patterns of selection in wild systems and their theoretical implications” would also have interested many of you here, as it addressed the question of variation in selection in natural populations, mentioned by Erik in his last post. Being a quantitative genetics conference, the talk was more focused on this side of the discussion, rather than the potential ecological drivers Erik mentioned below. The talk was also mainly focused on long-term studies of wild populations with pedigree data, such as the Soay sheep populations on St Kilda. He discussed the disparity between the estimates of directional selection in the wild, and associated lack of response. I found his discussion regarding the confounding statistical problems that come from tackling such issues, and the associated problems in such famous datasets as the Soay sheep, fascinating and a little disheartening.  It certainly backs up Erik’s argument that the answers to many of the big questions in evolutionary biology are not to be found in one discipline or using one approach.

Finally, I’d like to mention a talk given by Bruce Walsh on “The consequences of indirect genetic effects for heritable variation and response to selection”. Bruce was standing in for Piter Bijma, who had to leave the conference early and was unable to give his talk. Bruce presented Piter’s slides, giving his own version of the talk. It was an outstanding presentation and I wish I could get him to give all my future talks. It left me feeling quite inadequate, but that is something my therapist and I will have to deal with.

It was certainly an enjoyable conference and gave me the chance to meet many excellent scientists, which resulted in some great chats over some lovely single malt whisky. I am always astounded how many issues can be solved after a few glasses of scotch, if only I could remember what was decided. (all pictures are taken from the ICQG site)


  1. Great and interesting post Tom! It seems like a very interesting conference, and it was nice to get direct report. Especially, Mark Blows talk would have been interesting to hear.

  2. Thanks Tom for this post, it was an interesting read. And yes, I can relate to your feeling of feeling 'inadequate' at these gatherings. Hopefully this will pass at one stage. Keep it up!