Taking into account the importance of the role that genetic recombination plays in evolution, adaptation, survival, and – perhaps most importantly – sex, we know surprisingly little about the molecular foundations of this phenomenon. What we do know is that genetic recombination is not a completely random process; that it follows a pattern. Some chromosomal regions are more, and some less, likely to be affected by double-stranded breaks – and the recombination events that follow. Areas with a high frequency of recombination have been appropriately dubbed ‘recombination hotspots’.

Now, recombination hotspots are a bit of an enigma themselves: for a long time no one could put their finger on how these hotspots are defined – or chosen. But, as it …

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There is something amazingly captivating about turtles: those slow, long-living, hard-shelled creatures, which look very much like how you’d expect a miniature version of some dinosaur to look. They have inspired artists for many years, and continue to do so, from the Mock Turtle in Lewis Caroll’s Alice’s Adventures in Wonderland, through the impressive, world-carrying Great A’Tuin in Terry Pratchett novels, to the symbols of late 20th century pop-culture that are the Teenage Mutant Ninja Turtles. Turtles are enigmatic and elegant, reason enough for their study; with many turtle species on the brink of extinction, however, the need to capture the full scope of their biology becomes more urgent. It is perhaps surprising, therefore, that turtles …

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Looking at the problem of sex determination from our anthropocentric perspective, it is easy to forget that the world doesn’t revolve around the Y chromosome. Some animals determine their sex simply by changing the number of X chromosomes (BFF of many Genome Biology readers, C. elegans, belongs to this group). For others, like crocodiles and some turtles, the sex will be determined by the temperature at which the egg incubates. The platypus has 10 sex chromosomes, but, surprisingly, seems to lack the sex-determining SRY gene. And then there is the ZW sex chromosome system in birds, in which the sex of the offspring depends on the ovum and not the sperm.

This is not the only difference between us and …

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On the list of humanity’s priorities, tissue regeneration finds itself near the very top; together with eternal youth and immortality. And, in legends and myths, both heroes and villains – but most commonly monsters – possess an amazing ability to grow back lost organs and limbs.

Myths can have a grain of truth, though. In 2011, Genome Biology published an article describing the transcriptome of the regenerating head of a planarian flatworm, Schmidtea mediterranea. In early 2012, we published another article seeking to unveil the intricacies of regulatory mechanisms governing flatworm regeneration.

Fortunately, we don’t have to look that far down the evolutionary line to find species capable of tissue regeneration.  Much more complex organisms can be found as …

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So you have just spent the last couple of years on the project: using shiny brandnew machines to sequence the most complex genomes on Earth. You dotted your ‘i’s, crossed the ‘t’s, identified all ‘g’s and ‘c’s. From the (still growing) range of the available assemblers, you picked the one you thought best. And you ended up with the assembly that might be perfect, but might just as well be a disaster waiting to happen.

Both genome assemblies and assemblers can be assessed using a number of different quality metrics. For a long time, N50 was a leading metric used for that purpose but, although N50 scaffold and contig lengths most of the time correlate with assembly quality, the measure …

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In 2011 Arumugam et al. described for the first time characteristic patterns of human gut microflora composition, which were seemingly preserved world-wide, across different nations and cultures. These patterns, named enterotypes, were defined by the significantly higher abundance of one of three bacterial genera: Bacteroides (enterotype 1), Prevotella (enterotype 2) and Ruminococcus (enterotype 3).

This simple concept of enterotypes has since divided the microbiome field. Some researchers found themselves influenced by the alluring idea of discrete microflora types, while others dismissed it out of hand as overly simplistic and as blurring what they view as a more accurate, continuous image of our gut flora. It seems, however, that at this stage it is simply a bit too early to …

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