iGEM is a competition for conducting research on topics in synthetic biology, but what exactly is synthetic biology? Synthetic biology is a scientific discipline where multi-gene DNA sequences are added to well characterized organisms in order to understand biological behavior or to achieve a pre-determined function. Usually this is done by changing things inside a bacterial or eukaryotic cell, known as a biological chassis. Synthetic biology has many applications in therapeutics, biosensors, bioenergy, bioremediation, chemicals, and so on. To understand synthetic biology, let’s start by talking about the central dogma of molecular biology, which governs the way that genetic information in processed in all living cells. In the central dogma, deoxyribonucleic acid, or DNA, is converted to ribonucleic acid, or RNA, by a process called transcription and then that RNA is converted to proteins by a process called translation.

DNA and RNA are both nucleic acids. Think of DNA like your hard drive and RNA as a memory stick. Genes in your DNA are like files on your computer’s hard drive which need to be copied on a memory stick, that is RNA, in order to be transported somewhere else. During transcription, which is the first step of gene expression, DNA is copied into RNA by an enzyme called RNA polymerase.

In the second step of the central dogma, a messenger RNA is decoded by cellular ribosomes to produce a polypeptide, which is a specific chain of amino acids, which later fold to become an active protein. Ribosomes help decode an mRNA sequence by inducing the binding of specific molecules known as tRNAs with complementary anticodon sequences to that of the mRNA. A codon is a three nucleotide long sequence of DNA or RNA that encodes for a specific amino acid or for the stop or start of a polypeptide sequence.

Of course, this is a very simplistic overview of what the central dogma entails. In reality, there are many other molecules involved in the creation of functional proteins from DNA. With an understanding of basic molecular biology, you can start designing systems for making new proteins that have the functions that you are looking for. This is the start of synthetic biology.