Xenobiology is the study of strange (from the Greek word xenos) biology. It is closely related to exobiology and astrobiology, which concern themselves with seeking life forms not native to Earth. Xenobiology, however doesn't look to other planets for 'strange life', it attempts to create it in a lab. The aim is not just to make life forms which look different from what we're used to, but which don't have deoxyribonucleic acid (DNA) or ribonucleic acid (RNA) at all.

DNA is an acid inside a gene, the 'blueprint' for the cell, and RNA is a 'photocopy' of that blueprint. Cells use the photocopy as instructions on how to divide and make more cells. These acids exist in all life forms on Earth, from humans to trees to bacteria. They are responsible for how every living creature looks and how their bodies work.

Xenobiologists are attempting to create a whole new type of blueprint-carrying acid, tentatively called XNA, therefore creating a truly alien creature unlike anything on Earth at the most fundamental level.

This is done through various techniques, including through constructing the aforementioned XNA. There have been a number of successful breakthroughs in this area, like the creation of hexose nucleic acid (HNA) and glycol nucleic acid (GNA). Another method is to expand DNA. DNA is a code which contains four bases, A,T,G, and C, which correspond with different chemicals, arranged in various ways to spell out instructions. Scientists are experimenting with adding two more chemicals, termed P and Z, to create new DNA with six bases instead of just four. Initial results have been successful, but there is still a long way to go.

It's fitting that the term 'Xenobiology' was coined by a science fiction author, Robert Heinlein, as it deals with ideas which almost seem like science fiction.

The most obvious application of Xenobiology is to answer fundamental questions about where life came from, and how we evolved into modern humans. By understanding DNA and RNA, and by trying to bypass them entirely, scientists can figure out why our building blocks are the way they are, and potentially solve the puzzle of how life came to be on Earth.

Another purpose would be to see if life on other planets was theoretically possible. If scientists are successful in creating living creatures with a different chemical composition than those on Earth, it would mean that extraterrestrial life does not need Earth-like conditions to flourish.

The most pragmatic purpose of Xenobiology is the "genetic firewall." Synthetic biology-of which Xenobiology is a subset-is a larger field which deals with manufacturing and cultivating organic materials in a lab. However, synthetic biologists work with traditional DNA and RNA structures. In that case, there is a danger that if they create a dangerous microbe or bacterium, it could leak out of the lab and contaminate humans, or itself be contaminated by a technician with a cold. If xenobiologists succeed in creating a truly divergent life form, then it's likely that it would be unable to infect humans. This could push medicinal research, manufacturing, and genetic engineering, to whole new levels.

Related Links: Science Biology Branches of Biology