Mutation of somatic cells then only affects the "host" or humar within which they occur; mutation of "sex" cells may result in mitation of the newly created human, in early or late death, or in the transmission of these mutations to later generations resulting in i1tness, feebleness, or death. When the male sex cell (spermatazoa) is united with the female sex cell (ovum),the chromosomes and genetic material begin going through a uniting and dividing process which insures that every cell in our bodies contains half of our mother's and half of our father's chronosomes. If, however, the genetic material is damaged, for instance by ionizing particles, then, instead of reproducing themselves perfectly, they will produce defective cells which result in mutations, or changes, from the originally intended form. Mutation is no stranger to mankind. called individual variation. It is responsible for what is This is shown by differences in size and Weight, color of hair and skin, and shape of nose, mouth, ears, eyes, etc. If there were no such thing as mutation, all human beings would look alike. But because small defects occurred, or "mistakes" (changes) were made during the replication processes, we find a great variety of variation within the human race. Man today, then, is the end product of millions of years of genetic change and mutation and in this sense it may be said that the genetic pool of the present population as a whole has benefitted from mutation even though it represents the deaths of many people. What, however, we are generally not aware of is that many if not most mutations are generally harmful to those who carry them and generally result in the death or the elimination of the recipient. Hemophilia