1Peroxisomal Diseases.- Historical Perspective.- The Normal Peroxisome.- Peroxisomal Disorders.- Concluding Remarks.- References.- 2X-Linked Immunodeficiencies.- Human X-Linked Immunodeficiency Syndromes.- Animal Models.- X-Chromosome Inactivation Patterns as an Indicator of Phenotype of X-Linked Immunodeficiencies.- Linkage Analysis.- Genetic Management.- References.- 3Genetic Mutations Affecting Human Lipoproteins, Their Receptors, and Their Enzymes.- Biosynthesis and Modifications of Lipoproteins and Apolipoproteins.- Lipoprotein Receptors: Structure, Function, and Genetic Variation.- Genetic Variation of Plasma Enzymes and Proteins Involved in Lipoprotein Metabolism.- Facilitated Exchange and Transfer of Lipid among Lipoprotein Classes.- The Role of Plasma Enzymes and Apolipoproteins in the Reverse Transport of Cholesterol.- Apolipoproteins: Structure, Function, and Genetic Variation.- Proteins Associated with Lipoprotein Particles.- Regulation of Apolipoprotein Synthesis.- Future Directions.- References.- 4Genetic Aspects of Cancer.- Chromosomal Localization of Recessive Oncogenes.- Allele Loss.- The Position-Dependent Approach to Gene Cloning.- Molecularly Characterized Recessive Oncogenes.- Tumor Suppressor Genes Close to Isolation.- Conclusions.- References.- 5Gaucher Disease: Enzymology, Genetics, and Treatment.- Clinical Classification.- Specific Organ System Involvement.- Pathophysiology.- Biochemistry.- Molecular Biology.- Molecular Biology of the Activator Proteins.- Therapeutic Prospects in Gaucher Disease.- Diagnosis.- Clinical Genetics and Prevention.- References.- Addenda.