Genetics: Genetic adaptation of the blind mole rat to life underground

The genome and transcriptome sequence of the blind mole rat is reported this week in Nature Communications. The study provides insight into the genetic basis for this species’ adaptation to the environmental stress associated with living underground and highlights genes that may be involved in cancer resistance.

The blind mole rat, Spalax galili, is a solitary mammal that lives in underground burrows which protect it from predators and unfavourable climatic conditions. Over time, this species has evolved to cope with the darkness, lack of oxygen and high pathogen exposure associated with their subterranean lifestyle.

Eviatar Nevo and colleagues sequenced the blind mole rat genome and transcriptome (the complete set of RNA expressed across the genome) and identified an overrepresentation of repetitive genetic elements and individual genes which they believe reflects the blind mole rat’s low oxygen environment, highly developed digging activity and lack of sight.

The team also report the positive selection of genes which may have evolved a mechanism to increase necrosis (cell or tissue death) and immune-inflammatory response, which could underlie the cancer resistance and anti-ageing characteristics observed in the blind mole rat. The work provides a basis for studying adaptive evolution in mammals.