Estimates are that about 5% of cells in your body mutate when they multiply and divide—the new cell fails to copy the pattern completely and accurately from the original desirable pattern. Every person’s DNA contains mutations that typically are quite harmless. Others, however, are harmful and may be responsible for triggering abnormal conditions and specific diseases. A mutation is simply a change in the spelling of a DNA sequence. What does that mean? It’s fascinating! Think of DNA as a genetic language that consists of a 64-letter (codons) alphabet that spells out the genetic code. The letters are organized into words and sentences called genes - a segment of DNA passed down from parents to child that confers a trait to the offspring. Humans have 25,000-30,000 genes, usually in pairs (one from each parent). More tomorrow.