Chromosomes - The Complex Code

to the expression of oncogenes, which are pivotal in cancer genetics. Accurate delineation and prognosis of a cancer may depend upon careful cytogenetic analysis. Cytogenetics is still of great importance when monitoring changes in somatic cell hybrids. The role of chromosome genetics within modern biology is continually changing and evolving, and thus a knowledge of cytogenetics is of ever-increasing value. Chromatin structure 1 and replication Summary It is now a well-known fact that DNA is the hereditary material and that the vast majority of the DNA of an organism is housed in organelles called chromo somes. However, the length of DNA contained in a cell is far greater than the size of the cell within which it exists; for example, the shortest human chromosome consists of 1. 4 cm of DNA which must be compacted into a cell only a few micrometres across. To achieve this, DNA has to undergo several levels of packing, a process that is a mixture of DNA-DNA and DNA protein interactions. The most compact form of DNA can be seen under the light microscope as a meta phase chromosome during mitotic cell division. DNA must also be faithfully replicated to ensure accurate cell function and maintenance of the organ ism as well as ultimately, the reproduction of the species. Our current knowledge of these complex processes is very limited, with huge gaps, in particular, concern ing the links between the molecular and organelle level of organization.

List of contents

1 Chromatin structure and replication.- 1.1 Chromosome structure.- 1.2 Evidence that DNA is the genetic material.- 1.3 The double helix.- 1.4 The genetic code.- 1.5 DNA constitution.- 1.6 Higher order structure of DNA.- 1.7 Chromosome replication.- 2 Chromosome form and function.- 2.1 Structures in a chromosome.- 2.2 Heterochromatin.- 2.3 Telomeres.- 2.4 Centromeres and kinetochores.- 2.5 Nucleolar organizing regions.- 2.6 Lampbrush and polytene chromosomes.- 2.7 Double minutes and homogeneously staining regions.- 2.8 B chromosomes.- 2.9 Supernumerary segments.- 2.10 Artificial chromosomes.- 3 Chromosome identification.- 3.1 The karyotype.- 3.2 Chromosome banding.- 4 Nuclear division.- 4.1 Mitosis.- 4.2 The spindle apparatus.- 4.3 Meiosis.- 4.4 Chromosome pairing.- 4.5 Synaptonemal complex formation.- 4.6 Recombination nodules.- 4.7 Recombination and gene conversion.- 4.8 Meiosis in polyploids and structural rearrangements.- 4.9 Structural changes.- 5 Gene control by position and origin.- 5.1 Chromosome organization within the nucleus.- 5.2 Chromosomal imprinting.- 6 Mutagenesis.- 6.1 General ideas about mutagenesis.- 6.2 Changes associated with the environment.- 6.3 Chromosomal aberrations.- 6.4 Aneuploidies.- 6.5 Mutations affecting cell proliferation.- 6.6 Translocations.- 6.7 Fragile sites.- 6.8 Transposable elements.- 7 Chromosome mapping.- 7.1 Introduction.- 7.2 Genetic maps.- 7.3 Cytological maps.- 7.4 Correlation between genetic and cytological/physical maps.- 7.5 Mapping strategies.- 8 Sex chromosome systems.- 8.1 Heteromorphic sex chromosome systems.- 8.2 Mammalian sex chromosome systems.- 8.3 X inactivation.- 8.4 Mammalian sex chromosome evolution.- 8.5 Other sex chromosome systems.- 9 Evolution and speciation.- 9.1 Hybrids and cultivars.- 9.2 Speciation by karyotype changes.- 9.3 Speciation in an ancient mammalian group.- 9.4 Evolution of the hominids.- 10 Artificial manipulation of genomes.- 10.1 Manipulation of whole chromosome sets.- 10.2 Manipulationof single chromosomes.- 10.3 Manipulation producing variable genome changes.- 10.4 Single-gene transfer.- 11 Historical aspects of cytogenetics.

Summary

Chromatin structure 1 and replication Summary It is now a well-known fact that DNA is the hereditary material and that the vast majority of the DNA of an organism is housed in organelles called chromo somes. However, the length of DNA contained in a cell is far greater than the size of the cell within which it exists;

Report

...an excellent introduction to cytogenetics covering chromosome structure and function, cell division, evolution, mutation, sex chromosome systems, and the artificial manipulation of genomes, with the emphasis on eukaryotes. - Aslib Book Guide; ...clear written style...accessible for the student audience...recommended as a reference... - The Biologist

Product details

• Authors: Clark, Andrew Clark, M Clark, M. Clark, W Wall, W. Wall
• Publisher: Springer Netherlands
• Languages: English
• Product format: Paperback / Softback
• Released: 06.12.2012
• EAN: 9780412555305
• ISBN: 978-0-412-55530-5
• No. of pages: 346
• Weight: 682 g
• Illustrations: X, 346 p.
• Subject: Natural sciences, medicine, IT, technology > Medicine > Non-clinical medicine