Provides a wealth of useful supplementary information, including a chronology of important scientific and technological advances from 1590 to the present, lists of useful internet sites and journals, and a sample table of genome sizes and gene numbers. New definitions reflect the vastly expanding nature of genetics; includes new information on genomics, genomic variation, genetic and physical maps, noncoding RNAs, stem cell breakthroughs, genetic disorders, organisms and viruses of genetic interest, and laboratory techniques.