During mitosis, the 23 pairs of human chromosomes condense and are visible with a light microscope. A karyotype analysis usually involves blocking cells in mitosis and staining the condensed chromosomes with Giemsa dye. The dye stains regions of chromosomes that are rich in the base pairs Adenine (A) and Thymine (T) producing a dark band. A common misconception is that bands represent single genes, but in fact the thinnest bands contain over a million base pairs and potentially hundreds of genes. For example, the size of one small band is about equal to the entire genetic information for one bacterium.
Most delinquents are children who have been abandoned by their fathers. They are often deprived also of the love and affection they need from their mother. Inconsistent parenting, family turmoil, and multiple other stresses (such as economic hardship and psychiatric illnesses) that flow from these disagreements compound the rejection of these children by these parents, many of whom became criminals during childhood. With all these factors working against the child's normal development, by age five the future criminal already will tend to be aggressive, hostile, and hyperactive. Four-fifths of children destined to be criminals will be "antisocial" by 11 years of age, and fully two-thirds of antisocial five-year-olds will be delinquent by age 15.