Secrets of the olm revealed (or at least some of them)
In collaboration with Danish and Chinese colleagues, Slovenian scientists have decoded the genome of the olm, a cave-dwelling animal also known as Proteus anguinus or, more colloquially, as the “human fish”.
The heads of the project in Slovenia, Dr Nina Gunde-Cimerman and Dr Rok Kostanjšek, point out that this could in future pave the way for the development of new therapeutic possibilities, such as wound-healing and the treatment of diabetes, as well as leading to a greater understanding of the causes of obesity.
One of the reasons why the olm’s genome is so interesting to scientists is that the animal can live for over 100 years and is able to survive long periods of fasting, followed by over-feeding, without damaging its organs. The olm also has exceptional regeneration capabilities – it is even able to regrow an amputated limb, as visitors to Postojna Cave were able to witness recently.
The decoded first version of the olm’s genome has revealed that it is 15 times longer than the human genome, making it the longest genome sequenced so far.
The olm (Proteus anguinus), or “beli močeril” as it is also known in Slovenia, is the sole representative of the Proteidae family in Slovenia; it is also the only vertebrate in Europe that lives entirely in caves, although specimens are found in surface watercourses that flow from caves only after heavy rain, when the rising water carries away those olms that have not managed to find a safe place in time. The olm lives exclusively in underground waters and is well-adapted to life in complete darkness. It senses its surroundings using smell and by picking up vibrations, which it receives via sensory organs in the skin. Being of no use in a pitch dark environment, the olm’s eyes are atrophied and covered with skin. However, the animal can sense light throughout the whole of its body. Scientists hope that by studying the olm’s genome, they will be able to locate the genes that determine the animal’s sex. At the moment, they are unable to distinguish male and female, unless they spot eggs in the female.
This is a rare occurrence, but one we were able to witness three years ago in Postojna Cave, where 22 growing young olms, affectionately called “little dragons”, are still on show.