Seven times bigger than human. This is the genome of the most important commercial tree species in the United States, the taeda pine ( Pinus taeda ), which has just been sequenced by a team of scientists from the University of California.
“It is a great genome. But the challenge has not been only to collect the data of the sequence. The biggest problem was the assembly of that sequence in order “, explains to the scientific news agency SINC David Neale, researcher who has directed the study . And it is that this achievement has laid the first stone to use an analysis system that accelerates the assembly of the genome, which would allow the genes to be sequenced faster even if they are longer.
Initially it seemed that the objective that the research team had set itself was practically impossible. In the words of one of the team’s directors, Steven Salzberg, professor of medicine and biostatistics at Johns Hopkins University (USA), ” we were able to assemble the human genome, but it was close to the limit of our capacity, seven times bigger was just too much . ” However thanks to a new system, science has been overcome once again.
The method developed at the University of Maryland (USA) compiles fragments of sequence into much larger chunks by overlapping, and then discards that redundant information . Thanks to this elimination of redundancies, it is possible to process only the really important amount of data, that is, 100 times less data sequence.
But if pines are, at first glance, much simpler than humans, how can it be that their genome is so large? The study has confirmed that the genome of this pine is so immense because it is packed with invasive DNA elements that copy themselves throughout the genome. In fact, according to the researchers’ calculations, approximately 82% of the genome is made up of these and other repetitive fragments of sequence.
The sequencing also revealed the location of certain genes that may be involved in fighting pathogens, which will help scientists better understand disease resistance in pines.
The research has been published in the specialized scientific journal Genome Biology .
