Time: Thursday 15 April, 1115 - 1200
Place: Agricultural University of Norway - NLH, Auditorium H185, Animal Sciences Building
Speaker: Dr. Christian Klingenberg, School of Biological Sciences, University of Manchester, UK
Dr. Klingenberg's main area of research is how morphological variation comes about, and his primary model systems are the Drosophila wing and mouse mandible. Dr. Klingenberg will be visiting CIGENE from 14 to 16 April, and during his stay will give a talk entitledMorphological integration of QTL effects in the mouse mandible: developmental basis and new analytical approaches
The traits of organisms are integrated to function in the whole individual, but smaller complexes of traits form modules that have a certain degree of independence of each other. In this seminar, the developmental and genetic basis of this structured integration will be discussed using the mouse mandible as a model system. Genetic variation is considered through the analysis of quantitative trait loci (QTLs), but phenotypic variation is considered as well. Shape is characterised using the methods of geometric morphometrics.
Covariation among traits can originate through different developmental mechanisms. To delimit morphological modules as the domains within which direct developmental interactions play an important role, it is possible to analyse the patterns of covariation between left-right asymmetries of traits. These analyses confirm the hypothesis that the mouse mandible is subdivided into anterior and posterior modules (alveolar region and ascending ramus). However, the analysis also points out that this modularity is not all-or-nothing, but is a matter of degrees.
The same analyses can be used to investigate integration and modularity of QTL effects. The patterns of covariation are similar to those in the analyses of correlated asymmetry, suggesting that direct developmental interactions may play a significant role in the origin of pleiotropy. The patterns of QTL effects are also consistent with the hypothesis of two modules.
Theoretical considerations suggest that pleiotropy by direct interaction of developmental pathways may have a substantial influence on the patterns of genetic variation in natural populations and their evolutionary dynamics.
More information on Dr. Klingenberg's background and work can be found on http://www.sbs.man.ac.uk/staff/user.asp?id=1793&item=Research
