AbstractsBiology & Animal Science

Note: Missing Page 135. One of the main unsolved problems of medicine today is the fact that the frequency of human congenital malformations has shown no reduction in spite of the recent spectacular advances in understanding and treatment of human disease. The twentieth century has seen the successful application of the Mendelian laws to problems of disease transmission in man, leading to the brilliant elucidation of gene action in biochemical terms exemplified by the inborn errors of metabolism (Garrod, 1923) and the abnormal hemoglobins (Ruchnagel and Neel, 1962) and the development of refined methods to study the morphology of human chromosomes, leading to the identification, within the last few years, of a new group of human diseases, the chromosomal aberrations.