Extracting DNA: separating the wheat from the chaff

By Andrew Farrer

Reading the sequence of DNA molecules (the order of As, Gs, Cs, and Ts) is how ACAD researchers reconstruct the history of life. However, life at a cellular level is an intricate dance of simple and complex molecules – proteins, fats, carbohydrates – all working in concert to keep cells alive. DNA is part of this dance, the sheet music from which the music is read, providing the master copy of instructions for complex molecules such as enzymes. To ensure each of these molecules is made only when they’re needed, the DNA is not free-floating, but bound, packaged, and carefully regulated. Unfortunately, sequencing machines can only deal with pure DNA; all those other molecules will cause critical errors. So first we must separate the DNA wheat from the chaff by doing a DNA extraction.

Figure 1: Wheat seed heads. Before the wheat grains can be used, the tough dry cases enclosing them – the husk or “chaff” – must be removed. Credit: Dako99.

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LabARTory – the art of science architecture

By Andrew Farrer

I didn’t make a mistake; I intentionally used Bing. I learnt two interesting things from this: Firstly, it’s amazing how a different search engine introduces you to a very different range of information. Secondly, a lot more thought went into the artistic design of the ACAD ancient DNA lab than I had ever suspected.

OAGR: a brand new genome database

By Jimmy Breen and Andrew Farrer

Here at ACAD, the incredible range of rare, ancient samples we get to work with always excites us. The DNA data we are able to recover from these samples, alongside their crucial contextual information, reveals amazing insights into our history. We also realise that sharing data allows all researchers to ask bigger, broader, more detailed questions, and gives us the ability to answer them in more depth.

I hope you remembered to shower

By Andrew Farrer

A fairly common statement, perhaps, but at ACAD remembering to shower is not just about the risk of offending your workmate’s sense of smell, not showering could ruin a project and destroy precious samples. Contamination is a major risk for any DNA analysis but is particularly true for highly degraded DNA specimens, such as ancient DNA or forensic samples. Even small amounts of modern DNA entering your sample can be disastrous for a project. In order to overcome this, ACAD has a purpose-built ancient-DNA lab, self-contained and kept hyper-clean, especially for the analysis of highly degraded DNA.