Edward Kim Oxford Academy 10th Grade
Studies in science are becoming more advanced and detailed. Will diabetes be the next major breakthrough? Or perhaps cancer? As with these examples, more scientific studies depend upon animal models. Animal models are non-human animal species that are used to help scientists understand biological phenomena. In the case of the diseases listed above, animal models have traditionally been used to test certain drugs for a possible cure. Although traditional animal models have included mammals (e.g., mice to monkeys) with a similar genome to that of a human, new developments in laboratory research have been increasingly using a model for humans that doesn’t even have a vertebrate: the humble C. elegans.
Caenorhabditis elegans, or C. elegans for short, is a non-parasitic nematode roundworm that lives under the soil for all of its life. Although only a few millimeters long, C. elegans has some unique traits that make it perfect for an animal model. First, C. elegans hold the unique distinction in the field of biology for being the first multicellular organism to have its species genome completely sequenced. Because all of its genes and genetic pathways are completely known, C. elegans also is one of few animals species that has its entire developmental sequence mapped out. For example, scientists know that exactly 1090 cells will be formed during C. elegans’ development, 131 of which are destined for apoptosis or preprogrammed cell death.
While this may seem impressive on its own, knowing the entire genome of C. elegans becomes invaluable when one considers its similarity to humans. Despite being a roundworm, roughly 35% of C. elegans genes are very close to human genes, a staggering amount when a) one considers the fact that C. elegans has close to 22,000 genes in its genome and b) how different the nematode is in both shape and way of life from a human. The similarity in genetic sequence makes the C. elegans a very viable model for studies in specific human genes.
Besides its genetic capability to be an animal model, C. elegans also is perfect as an animal study in its physiological traits. C. elegans has not only has a small body size but also a fast generation cycle; growing from a larvae to an adult takes less than a month. This allows scientists who wish to study an experiment over generations to obtain more research without having to wait for long periods of time. C. elegans also has relatively simple nutritional needs, needing only small amounts of E. colibacteria to keep it satiated. It is the perfect portable animal model. C. elegans is a completely transparent nematode, meaning that light from a microscope can pass directly through it. This makes it ideal for scientists who wish to study the internal structures of C. elegans as it moves.
Current animal models that are used for human model studies are far from perfect. Mice, for example, have been the model of choice for decades but with high maintenance costs and a tendency to not be able to accurate model human diseases. As a portable and surprisingly homologous invertebrate, C. elegans may become a more popular animal model to study in the years to come due to its propensity as an animal model and its charted genetic pathways.
<Edward Kim Oxford Academy 10th Grade