This volume of Advances in Genetics furthers the serial's goal of presenting topics of interest to both human and molecular geneticists. Topics of interest in this volume include: Expression patterns of regulatory genes and the role they play in development Hereditary ataxias and specific disease states where the genetic defect has been identified Minute genes, their mutations, and their molecular function in Drosophila The genetics and molecular biology of rhythm mutants and clock molecules Double strand breaks in DNA and their repair mechanisms Key Features * Expression patterns of regulatory genes and the role they play in development * Hereditary ataxias and specific disease states where the genetic defect has been identified * Minute genes, their mutations, and their molecular function in Drosophila * The genetics and molecular biology of rhythm mutants and clock molecules * Double-strand breaks in DNA and their repair mechanisms and lack of repair mechanisms resulting in human disorders