The importance of DNA and its structure and function are central to the UK science curriculum at every level of education from the age of 12 upward.
This protocol achieved an increase in DNA yield using readily available equipment and reagents at a lower per capita cost and is simple to use. The DNA was then precipitated with sodium chloride and absolute ethanol. Protein was then digested using Proteinase K (Qiagen Inc., UK) at 56☌ for 10 min. Lysis was achieved using a TE (10 mM Tris-HCl, 1 mM EDTA, pH 8) + 1% Sodium Dodecyl Sulphate (SDS) buffer. The optimum protocol used an isotonic Lucozade Hydro Active Fitness Water (HAFW) mouthwash. A validation study was undertaken with the optimized protocol to assess its performance when conducted by a group of students in a classroom setting.
To identify the optimum conditions for each stage of the protocol (cell harvest, lysis, purification, and precipitation), each was investigated separately, and an adaptation of the fast-boiling protocol was used for the remaining stages. Seven criteria were established to evaluate the protocol: Safety, DNA yield, DNA quality/stability, cost, user friendliness, reliability, and time. Buccal mucosal epithelia provide a readily available source of cells for DNA extraction and can be harvested in a painless, noninvasive manner. A cost effective, simple protocol for DNA extraction and visualization was devised. Students gain a sense of ownership and are more enthusiastic when they use their own DNA. DNA extraction provides a hands-on introduction to DNA and enables students to gain real life experience and practical knowledge of DNA.