What makes DNA profiles useful?
What makes DNA profiles useful?
Most human DNA is the same from person to person, so DNA profiling focuses on the smaller regions that vary a lot. These are often non-coding short tandem repeats or STRs, where a short base sequence is repeated a different number of times in different people.
Step-by-step lessons on Edexcel A A Level Biology DNA profiling, PCR and gel electrophoresis. Each one builds up to exam-style questions. Build a strong foundation in cell biology and biochemistry early on, since later topics on genetics, ecology and physiology all draw on these core concepts.