DNA analysis. Researcher examining the results of an analysis of a sample of deoxyribonucleic acid (DNA). This is a microarray analysis where known genes (sections of DNA) are compared to a sample. When they match, the genes bind to the site on the microarray, forming a coloured dot. These dots are seen on the photographic film being held by the researcher. DNA is found in cell nuclei. Each individual has a unique genetic profile that can be used to identify them. Microarray analysis techniques are often used to study gene expression, or to detect genetic mutations. Sample vials are seen at right. Photographed in France.