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Background Identification of homologous regions or conserved syntenies across genomes is one crucial step in comparative genomics. This task is usually performed by genome alignment softwares like WABA or blastz. In case of conserved syntenies, such regions are defined as conserved gene orders. On the gene order level, homologous regions can even be found between distantly related genomes, which do not align on the nucleotide sequence level. Results We present a novel approach to identify regions of conserved synteny across multiple genomes. Syntenator represents genomes and alignments thereof as partial order graphs (POGs). These POGs are aligned by a dynamic programming approach employing a gene-specific scoring function. The scoring function reflects the level of protein sequence similarity for each possible gene pair. Our method consistently defines larger homologous regions in pairwise gene order alignments than nucleotide-level comparisons. Our method is superior to methods that work on predefined homology gene sets (as implemented in Blockfinder). Syntenator successfully reproduces 80% of the EnsEMBL man-mouse conserved syntenic blocks. The full potential of our method becomes visible by comparing remotely related genomes and multiple genomes. Gene order alignments potentially resolve up to 75% of the EnsEMBL 1:many orthology relations and 27% of the many:many orthology relations. Conclusion We propose Syntenator as a software solution to reliably infer conserved syntenies among distantly related genomes. The software is available from http://www2.tuebingen.mpg.de/abt4/plone.

Background Higher eukaryotes control the expression of their genes by mechanisms that we are just beginning to understand. A complex layer of control is the dynamic spatial organization of the nucleus. Results We present a bioinformatics solution (3PD) to support the experimentalist in detecting long-ranging intra or inter chromosomal contacts by Chromosome conformation capture (3C) assays. 3C assays take a snapshot of chromosomal contacts by a fixation step and quantify them by PCR. Our contribution is to rapidly design an optimal primer set for the crucial PCR step. Our primer design reduces the level of experimental error as primers are highly similar in terms of physical properties and amplicon length. All 3C primers are compatible with multiplex PCR reactions. Primer uniqueness is checked genome-wide with a suitable index structure. Conclusions In summary, our software 3PD facilitates genome-wide primer design for 3C experiments in a matter of seconds. Our software is available as a web server at: http://www.pristionchus.org/3CPrimerDesign/.