FEAT U R ES
Nathan Pitt, University of Cambridge
Features
Decoding DNA by Next Generation Sequencing Shankar Balasubramanian (1994) I returned to Cambridge in early 1994, having spent a couple of years in a lab in the USA. When I started my independent laboratory in the Department of Chemistry at Lensfield Road, I set out to explore a number of different problems, each at the interface of chemistry and biology. Looking back, I might interpret this phase as either being pioneering and exploratory, or one where I didn’t really know what I wanted to pursue. Being in Cambridge it was perhaps inevitable that I would soon converge on the study of DNA, which I have stuck with ever since. My current research explores the nature of alternative folded DNA secondary structures and the natural chemical modification of DNA. Here, I will focus on some early work that led to a method for reading the DNA code very quickly, which is now widely used.
DNA DNA is a linear, natural polymer made up of four building blocks (called nucleotides) that each carry a base, often abbreviated by one of the four letters G, C, T and A. The most common structural form of DNA is a right-handed, double helix made up of two strands, which is in large part due to the molecular recognition of the bases in two well-defined pairing patterns, G recognises C to form a G:C pair and T recognises A to form a T:A pair, often called Watson-Crick base pairing (Figure 1). This pattern of recognition of DNA bases provides the
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