Static and Dynamic Properties of DNA Languages

We provide an overview of some current developments on code-related properties of DNA languages. A DNA language is a set of words, each of which is made up of the letters A, C, G, T. Such a word is meant to represent a physical DNA strand. A collection of DNA strands can be stored in-vitro and, either serve the purpose of a database, or undergo a sequence of controlled hio-operations that would constitute a meaningful computation. In both cases, the strands should be chosen in such a way that they would not form unwanted hybridizations with each other and any errors in the nucleotides comprising the strands can be detected. These requirements can he translated in the framework of formal language theory by considering DNA languages whose words satisfy certain combinatorial properties. We consider two types of desirable properties: static and dynamic. The former ensure that no unwanted hybridizations can occur. The latter ensure that, after a permitted bio-operation is applied to the strands, the resulting strands also satisfy the desirable properties. Keywords-DNA codes, DNA computing, formal languages