Genetics, Second Edition

Endeavours to make this seemingly difficult subject understandable and enjoyable for the readers. It provides an account of classical and modern genetics with new developments in the field. The scope of each chapter has been broadened enough to provide information on historical landmarks as well as of new facts from current issues of major journals. Chapters on gene transcription, regulation, human genetics, recombinant DNA and genomics have been given special attention to create awareness about future areas in this growing field. Experimental work is supported by methodologies and illustrations. The text is useful for students pursuing courses in cell and molecular biology, biophysics, anthropology and agricultural sciences at universities, medical colleges and similar institutions. New Age Publications (Academic) 8122423906 1 Dedicated to My Parents 6 Preface to the Second Edition 8 Preface to the First Edition 10 Contents 12 Chapter 1. The Pre-Mendelian Era and Mendelism 18 Mendel and the Birth of Mendelism 19 Mendel's Experiments 19 Selected Readings 27 Chapter 2. Interaction of Genes 28 Incomplete Dominance 28 Codominance 29 Epistasis 30 Complementary Genes 34 Duplicate Genes 35 Polymeric Genes 35 Modifying Genes 36 Lethal Genes 36 Questions 40 Selected Readings 41 Chapter 3. Environment and Gene Expression 42 Penetrance and Expressivity 42 Temperature 43 Light 44 Phenocopies 44 Environmental Effects and Twin Studies 45 Human Intelligence 46 Drug Resistance 46 Questions 46 Selected Readings 47 Chapter 4. Quantitative or Polygenic Inheritance 48 Inheritance of Kernel Colour in Wheat 49 Corolla Length in Tobacco 51 Skin Colour Inheritance in Man 52 Transgressive and Regressive Variation 52 Questions 53 Selected Readings 53 Chapter 5. Multiple Alleles 54 What are Multiple Alleles? 54 Sexual Incompatibility in Plants 55 Blood Group Alleles in Man 56 Multiple Alleles and Complex Loci 58 Questions 58 Selected Readings 59 Chapter 6. Cell Division and Chromosome Theory of Inheritance 60 Mitosis 60 Meiosis 63 The Chromosome Theory of Inheritance 72 Questions 74 Selected Readings 75 Chapter 7. Chi-Square Test and Probability 76 Chi-Square Test 76 Probability 78 Binomial Expansions 79 Multinomial Distributions 80 Questions 81 Selected Readings 82 Chapter 8. Linkage, Recombination and Gene Mapping 83 Morgan's Work on Drosophila 85 Crossing Over 87 The Three-Point Cross 88 Detection of Linkage 91 Double Crossing Over 91 Cytological Basis for Crossing Over 92 Sex Linkage 94 Recombination in Neurospora 96 Gene Mapping in Fungi 98 Questions 101 Selected Readings 102 Chapter 9. Extranuclear Transmission of Traits 104 Killer Trait in Paramecium 105 CO2 Sensitivity in Drosophila 106 Plastid Inheritance 107 Male Transmission in Geranium (Pelargonium) 108 Iojap Strain of Maize 108 Male Sterility in Plants 108 Inheritance Through Mitochondria 109 The Genetics of Mitochondria and Chloroplasts 110 Extranuclear Genes in Chlamydomonas 111 Questions 112 Selected Readings 113 Chapter 10. The Genetic Control of Sex 114 Chromosomal Basis of Sex Determination 115 Sex Chromosomes in Resting Nuclei: Barr Bodies and Lyon's Hypothesis 117 Balance Theory of Sex determination 119 Sex Mosaics 121 Genotypic Mechanisms for Sex Determination 122 Environmental Control of Sex 123 Hormones and Sex Determination 124 Questions 125 Selected Readings 125 Chapter 11. Variations in Chromosome Number 127 Euploidy 127 Artificial Induction of Polyploidy 132 Aneuploidy 133 Aneuploidy in Drosophila 135 Aneuploidy in Humans 136 Haploids 136 Questions 137 Selected Readings 137 Chapter 12. Variations in Chromosome structure 139 Deletion Or Deficiency 139 Duplications 142 Translocations 144 Inversions 151 B-Chromosomes 153 Questions 154 Selected Readings 154 Chapter 13. Nature of the Genetic Material 156 DNA is The Genetic Material in Bacteria 156 Evidence That DNA is The Genetic Material in Viruses 158 Genes of Some Viruses are Made of RNA 160 Biochemical Evidence That Genes are Made of DNA 161 Questions 162 Selected Readings 162 Chapter 14. The Structure and Replication of DNA 163 Types of Bonds 164 The Double Helix 165 The A, B and C Forms of DNA 168 The Left Handed Helix 168 Bends in DNA 169 Supercoiled DNA 170 Replication of DNA 170 The Nucleic Acid Enzymes - A General Account 173 Molecular Mechanism of DNA Replication 174 DNA Replication in Bacteria 176 DNA Replication in Eukaryotes 179 Replication in Kinetic Classes of DNA 181 The Rolling Circle Method of Replication 181 Replication in DNA Viruses 182 Questions 182 Selected Readings 183 Chapter 15. Gene Transcription and Translation into Proteins 185 The Central Dogma 185 Colinearity of Gene and Its Product 187 Transcription 188 Eukaryotic Transcription 194 Messenger RNA 197 Reverse Transcription 202 RNA and Protein Synthesis 203 Transfer RNA 204 Ribosomes and Ribosomal RNA 205 The Reconstitution of Ribosomes 208 Special Features of rRNA Genes 209 The Genetic Code 209 Genetic Evidence for The Code 213 Translation and Protein Biosynthesis 215 Destinations of Proteins 222 Open Reading Frame 225 Functional Proteins 225 Questions 228 Selected Readings 229 Chapter 16. Genetic Regulation in Prokaryotes and Eukaryotes 231 What are Induction and Repression? 231 Regulation in Prokaryotes 232 Details of Genes 234 The Inducible and Repressible Systems 236 Transcriptional and Translational Control 237 DNA Methylation 245 Questions 247 Selected Readings 248 Chapter 17. Genetics of Bacteria 250 Transformation 251 Conjugation 254 Transduction 258 The Genetic MAP of E. coli 260 Plasmids 261 Moveable Genes 262 Genomes in Mitochondria and Chloroplasts 264 Questions 268 Selected Readings 268 Chapter 18. Genetics of Viruses 270 Life Cycle of Virulent Bacteriophages 271 Temperate Phages and Prophage 273 Genetic Recombination in Phages 274 Mapping Genes in Phage Lambda 277 The RNA Phages 279 Tumour Viruses and Cancer 280 Viroids 283 Questions 283 Selected Readings 284 Chapter 19. The Eukaryotic Chromosome 285 Gross Structure of Chromosomes 285 The Nucleolus 291 Some Specific Gene Sequences in Chromosomes 295 Chromosome Banding 296 The Synaptonemal Complex 297 Strandedness of Chromosomes 299 Chromosomal Proteins 299 The Nucleosome 300 The Supranucleosomal Structures 302 The Specialised Chromosomes 303 Questions 305 Selected Readings 305 Chapter 20. Mutations 308 Detection of Spontaneous Mutations 309 Cytologically Visible Gene Mutations 312 Mutable Genes 312 Induction of Mutations 312 UV Radiation 315 Chemicals as Mutagens 316 Reverse Mutations 320 Repair of DNA 322 Sister Chromatid Exchanges 324 Mutations Affecting Human Beings 325 Environmental Mutagens and Carcinogens 325 Questions 326 Selected Readings 326 Chapter 21. Human Genetics 328 The Human Chromosome Complement 328 Chromosomal Anomalies and Human Disorders 329 Tracing The Gene in Family-Pedigree Studies 334 Genetics of Human Metabolic Diseases 338 Some Complex Traits in Families 341 Genetics of The Haemoglobins 342 Amniocentesis 344 Somatic Cell Hybrids 346 Immunogenetics 348 The HLA System 350 Cancer 354 Oncogenes 356 Human Prion Disease 361 Questions 362 Selected Readings 362 Chapter 22. Fine Structure of The Gene 365 Mapping The rll Locus in T4 366 Gene Conversion 370 Split Genes 375 Gene Families and Pseudogenes 377 Transposable Elements 378 Overlapping Genes 381 Questions 383 Selected Readings 383 Chapter 23. Recombinant DNA Technology 385 Questions 407 Selected Readings 407 Chapter 24. Applications of Recombinant DNA Technology 409 Selected Readings 421 Chapter 25. Genomics 422 Optical Mapping of Whole Genome 429 Synthetic Genomics 430 Selected Readings 430 Chapter 26. Populations and Gene Frequencies 434 Gene and Genotype Frequencies 434 The Hardy-Weinberg Law 435 Nonrandom Mating 437 Variation in Populations 439 Changes in Gene Frequencies in Populations 441 Selected Readings 443 Chapter 27. Origin of Life-Evolution of Man 444 Origin of The First Elements 445 Chemical Evolution 445 Geological Evidences 446 The Planets and Life 449 Prebiotic Synthesis of Macromolecules 451 From Micro-Organisms to Man 457 Darwin and Natural Selection 460 Selected Readings 460 Index 462 9788122423907,8122423906 About the Book: Endeavours to make this seemingly difficult subject understandable and enjoyable for the readers. It provides an account of classical and modern genetics with new developments in the field. The scope of each chapter has been broadened enough to provide information on historical landmarks as well as of new facts from current issues of major journals. Chapters on gene transcription, regulation, human genetics, recombinant DNA and genomics have been given special attention to create awareness about future areas in this growing field. Experimental work is supported by methodologie