Book contents
- Frontmatter
- Contents
- Preface
- 1 The history and evolution of the domestic fowl
- 2 The cellular organisation of genetic material
- 3 The transmission of inherited characters
- 4 Sex determination and sex-linked inheritance in the domestic fowl
- 5 Linkage and chromosome mapping
- 6 Genes controlling feathering and plumage colour
- 7 Muscle, nerve and skeleton
- 8 Lethal genes in domestic fowl
- 9 Quantitative genetics
- 10 Protein evolution and polymorphism
- 11 Immunogenetics of the domestic fowl
- 12 Gene cloning, sequencing and transfer in the domestic fowl
- APPENDIX I Linkage groups and the chromosome map in the domestic fowl
- APPENDIX II Oncogenes
- APPENDIX III The Chi squared (χ2) test
- APPENDIX IV One letter amino acid code
- APPENDIX V The genetic code
- Glossary
- Index
2 - The cellular organisation of genetic material
Published online by Cambridge University Press: 22 September 2009
- Frontmatter
- Contents
- Preface
- 1 The history and evolution of the domestic fowl
- 2 The cellular organisation of genetic material
- 3 The transmission of inherited characters
- 4 Sex determination and sex-linked inheritance in the domestic fowl
- 5 Linkage and chromosome mapping
- 6 Genes controlling feathering and plumage colour
- 7 Muscle, nerve and skeleton
- 8 Lethal genes in domestic fowl
- 9 Quantitative genetics
- 10 Protein evolution and polymorphism
- 11 Immunogenetics of the domestic fowl
- 12 Gene cloning, sequencing and transfer in the domestic fowl
- APPENDIX I Linkage groups and the chromosome map in the domestic fowl
- APPENDIX II Oncogenes
- APPENDIX III The Chi squared (χ2) test
- APPENDIX IV One letter amino acid code
- APPENDIX V The genetic code
- Glossary
- Index
Summary
The first sections of this chapter (2.1–2.3) form a résumé on the nature and functioning of genes, how they are organised and how they replicate. The second half (sections 2.4 and 2.5) then describes specifically the chromosomes in the domestic fowl, including chromosomal abnormalities.
The nature of the gene and its organisation on the chromosome
Since the turn of the century it has been apparent that genes are the units of inheritance and, since Watson and Crick's proposal in 1953 for the double helical structure of DNA, their molecular nature has been clear. However, there is still much to be learned about their organisation and also the details of replication and expression. Genes are comprised of DNA, a macromolecule having a double helical structure in which its two strands are arranged in antiparallel fashion. The information content of DNA arises from the specific order of the structural units attached to the backbone of the macromolecule; these structural units are known as bases. There are four different bases in DNA: adenine, thymine, guanine and cytosine, usually abbreviated to their first letters A, T, G, and C. Each gene may have as many as 1000 or more bases arranged in a unique sequence along the macromolecule.
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- Information
- Genetics and Evolution of the Domestic Fowl , pp. 15 - 34Publisher: Cambridge University PressPrint publication year: 1991