Researchers at the Royal Veterinary College (RVC) and the University of Kent have developed a new cost effective approach to mapping and assembling genomes, using a novel method that is particularly effective for bird species.

Developed with public funding, researchers said the new method will make it easier to map complete animal genomes (at the chromosome-level), which will improve understanding and could hasten advances in animal breeding.  

Genetics studies have long faced the major problem that although sequencing an animal genome is easy and cheap, assembling sequences to complete chromosomes level is difficult and expensive. Though this level of genome mapping is much more useful for genetic science, without sufficient funding it’s been too time intensive and costly to map a number of animal genomes in this way.  

As a result, most animal genomes that have been sequenced are not assembled to chromosomes level, and until the new method was published this week, only three bird species’ genomes had been mapped to the complete chromosome level.

The new method developed by the RVC and University of Kent Comparative Genomics teams allows geneticists to reach chromosome level genome assembly both cost-effectively and fast. The team’s specific breakthrough is to use universal probes to anchor scaffolds to chromosomes physically.

The method of using probes to map genomes has existed for a long time, but this research with contribution from the Cambridge companies Cytocell Ltd and Digital Scientific UK is the first to make a complete panel of universal probes that work equally well on any avian (and often even on reptile) genomes.

This means that once DNA has been extracted from about 250 probes, these can be used as universal probes, and it is possible to apply them to any avian genome equally successfully. It then becomes an extremely cost effective way of assembling a complete genome to chromosome level, relative to designing probe libraries, choosing probes, verifying and mapping them for each genome separately.

Although only three bird species’ genomes had been mapped to the more complete level before the study was published, using this novel method, the research team were able to map and assemble the complete genome of pigeons and the peregrine falcon, with all other bird species also easily accessible. They said this new method - even as it stands - could herald improvements for the farm industry, putting poultry species’ complete genomes within reach, and enabling diseases to be tackled at a genetic level

Birds were used to develop and test this method because avian and reptilian genome sequences are more evolutionary conserved than mammals, making it easier to select universal probes. Avian genomes are also three times smaller than mammals’. However, based on the success of this method, the research team will now attempt to apply the same approach to mammals.