基因 Chapter 4 The Content of the Genome.pdfVIP

The Content of the Genome CHAPTER OUTLINE .. Introduction The Conservation of Genome Organization Helps to 111 Genomes Can Be Mapped by Linkage, Restriction Identify Genes Cleavage, or DNA Sequence • Algorithms for identifying genes are not perfect and many corrections must be made to the initial data set. .. Individual Genomes Show Extensive Variation • Pseudogenes must be distinguished from active genes. • Polymorphism may be detected at the phenotypic level • Syntenic relationships are extensive between mouse and when a sequence affects gene function, at the restriction human genomes, and most active genes are in a syntenic fragment level when it affects a restriction enzyme target region. site, and at the sequence level by direct analysis of DNA. • The alleles of a gene show extensive polymorphism at the Organelles Have DNA sequence level, but many sequence changes do not affect • Mitochondria and chloroplasts have genomes that show function. non-Mendelian inheritance. Typically they are maternally inherited. lIB RFLPs and SNPs Can Be Used for Genetic Mapping