08 May 08

The platypus: a happy marriage of reptile and mammal

An international team, including Oxford scientists, has revealed the genetic make up of the platypus – giving fresh insight into the evolutionary history of mammals.

The platypus is one of the world’s strangest animals as it combines mammal characteristics, such as having fur and rearing its young on milk, with traits common to reptiles – the female platypus lays eggs whilst males produce venom.

Scientists have now found that the platypus genome is just as ‘mixed up’ as its odd combination of characteristics suggests with some genes resembling those found in birds and others reptiles, along with genes familiar from mammals. They report their findings in this week’s Nature.

Lead researcher Professor Chris Ponting from the MRC Functional Genomics Unit at Oxford said: ‘The platypus genome is extremely important because it is the missing link in our understanding of how we and other mammals first evolved. This is our ticket back in time to when all mammals laid eggs while suckling their young on milk. It also provides an essential background to future understanding of mammalian biology and evolution.’

The platypus genome came from a female nicknamed ‘Glennie’ and was sequenced by scientists from the Washington University School of Medicine, USA. Researchers from Oxford’s MRC Functional Genomics Unit and the European Molecular Biology Laboratory’s European Bioinformatics Institute in Cambridge then searched the DNA sequence for the genes responsible for the mixture of characteristics found in the platypus. The research was supported by the Medical Research Council (MRC).

More detail on the Oxford Science Blog.