DNA-Based Digital Storage

Digital data generation is increasing exponentially, and estimates suggest that the amount of new data being generated each year has already surpassed the data storage capacity of current technologies. DNA presents an alternative technology for the storage of digital information due to several attractive properties. DNA is an extremely stable molecule, it takes up very little physical space, and since it makes up the human genome, the technology needed to read it back will never become obsolete. We discuss the practical and technical issues being addressed to further develop DNA synthesis technologies, enabling use of DNA as a digital storage medium. We also offer a perspective on opportunities at the intersection of the synthetic biology and information technology industries, highlighting how the convergence of research in these areas will accelerate discovery in both. Modern digital computers store, communicate, and operate on binary data, represented as ones and zeroes. These bits of information are associated with physical structures and signals, such as the electronic state of transistors or field orientation of magnetic materials. Nature also stores digital information, such as the genetic code in your cells, in the form of molecular polymers. In DNA, these polymers are built from a set of four small molecules known as nucleotides, or bases for short (Fig. 1). Instead of just two values available with binary data (one or zero), each base position in DNA can take one of four values (A, C, G, or T, representing the chemical name of the base), so each base is essentially the information equivalent of two bits (Fig. 2). Each typical human cell contains a genome consisting of about 6 billion base pairs of double helical DNA, organized into 23 sets of chromosomes (3 billion base pairs of DNA correspond to the chromosomes in each half of the set). The DNA in these chromosomes encode about 1.6 gigabytes of information in total, per cell. Adding up all the phosphate pentose