Abstract
The preceding "The Human Genome" column described single gene associated diseases. Another theme will be dealt with in this column: the interaction of the numbers of genes needed to bring about some action. Such wholly-caused gene diseases are at one end of the spectrum. More likely, gene composition declares tendencies, some of these are somewhat random tendencies and others are related to our lifestyles-both voluntary and involuntary. Thus, single genes that dictate aggression, being good-natured, intelligence, criminal nature, etc. are not present. Most of our tendencies are just that-tendencies. Such tendencies are complex and involve the interaction of many genes and the associated proteins as well as external forces and opportunities.