Recent genomics studies confirm that as much genetic variation is due to structural genetic changes such as differences in gene copy number and chromosome rearrangements than as to single-nucleotide polymorphisms. In order to understand the evolution of that kind of genetic variation, one needs to investigate which chromosome arrangements occur in different species, and whether rearrangements are associated with life history differences between species or not.
In this project, we investigate the evolution of chromosomal structural genetic changes using South-American annual Austrolebias killifish as a model system.
The putative ancestral number of chromosomes for the genus is 2N = 48 acrocentric chromosomes (number of arms NF = 48). Austrolebias prognathus has 2N = 36 chromosomes, with NF = 48 arms, implying that several chromosome fusions have occurred. There are several more changes documented in the Austrolebias genus, but the picture is incomplete. We keep over 25 species of the genus in the lab, and already have a molecular phylogeny. The student can make karyotypes of all those species using cells from fin-clips, and map chromosomal changes observed in the karyotypes on the molecular phylogeny.
This is a project for a Master student.
Prerequisites: Some familiarity with handling fish and with lab techniques is advantageous, but not strictly necessary.
Supervisors: Tom Van Dooren (t.j.m.van.dooren@biology.leidenuniv.nl), Kees Hofker and Gerda Lamers (IBL Visualization).