On the Detection of Recombination in Minisatellite Data
Résumé
Tandem repeats are repeated sequences whose copies are adjacent along the chromosomes. They account for large portion of eukaryotic genomes and are found in all types of living organisms. Among tandem repeats, those with repeat unit of middle size are called minisatellites. These loci depart from classical loci because of the propensity to vary in size due to the adjunction or the removal of one or more repeat units. Because of this polymorphism, they prove useful in genetic mapping, in population genetic and forensic medicine. Moreover, some specific loci are involved in diseases, like the insulin minisatellite which is implicated in type I diabetes. Those loci also undergo complex recombination events. Presently, program to compare minisatellite alleles exist and yield good results when recombination is absent, but none treats correctly recombinant minisatellite alleles. Our goal is to develop an adequate tool for the detection of recombinant among the minisatellite sequences. By combining a multiple alignment tool and a method based on phylogenetic profiling, we design a first solution, called {\msp}, for this task. The method has been implemented, tested on real data sets from the insulin minisatellite, and proves to detect recombinant alleles.