Human Premature Aging Disorders and Dysfunction of DNA Repair -- DNA Repair Aspects for RecQ Helicase Disorders -- Trichothiodystrophy -- Roles of the BRCA1 and BRCA2 Breast Cancer Susceptibility Proteins in DNA Repair -- Radiosensitivity of Cells Derived from Down Syndrome Patients -- The Fanconi Anemia/BRCA Pathway -- Is Ataxia Telangiectasia a Result of Impaired Coordination between DNA Repair and Cell Cycle Checkpoint Regulators? -- Mechanisms of DNA Damage and Repair in Alzheimer Disease -- Orchestration of Telomeres and DNA Repair Factors in Mammalian Cells -- Defective Solar Protection in Xeroderma Pigmentosum and Cockayne Syndrome Patients.