A sound body depends on the continuous interplay of thousands of proteins, acting together in just the right amounts and in just the right places--and each properly functioning protein is the product of an intact gene.

Many, if not most, diseases have their roots in our genes. More than 4,000 diseases stem from altered genes inherited from one's mother and/or father. Common disorders such as heart disease and most cancers arise from a complex interplay among multiple genes and between genes and factors in the environment.