William S. Klug Michael R. Cummings Charlotte A. Spencer Concepts of Genetics Eighth Edition Chapter 8 Chromosome Mutations: Variation in Chromosome Number and Arrangement Copyright © 2006 Pearson Prentice Hall, Inc.

Specific Terminology Describes Variations in Chromosome Number

Table 8-1 Copyright © 2006 Pearson Prentice Hall, Inc.

Variation in the Number of Chromosomes Results from Nondisjunction

Figure 8-1 Copyright © 2006 Pearson Prentice Hall, Inc.

Monosomy, the Loss of a Single Chromosome, May Have Severe Phenotypic Effects Partial Monosomy in Humans: The Cri-du-Chat Syndrome 46, -5p

Figure 8-2 Copyright © 2006 Pearson Prentice Hall, Inc.

Trisomy Involves the Addition of a Chromosome to a Diploid Genome

Figure 8-3 Copyright © 2006 Pearson Prentice Hall, Inc.

Trisomy during meiosis Figure 8-4 Copyright © 2006 Pearson Prentice Hall, Inc.

Trisomy Involves the Addition of a Chromosome to a Diploid Genome Down Syndrome 47, +21

Figure 8-5 Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-6 Copyright © 2006 Pearson Prentice Hall, Inc.

Trisomy Involves the Addition of a Chromosome to a Diploid Genome Patau Syndrome 47, +13

Figure 8-7 Copyright © 2006 Pearson Prentice Hall, Inc. Patau Syndrome 1: 19,000

Trisomy Involves the Addition of a Chromosome to a Diploid Genome Edwards Syndrome 47, +18

Figure 8-8 Copyright © 2006 Pearson Prentice Hall, Inc. Edwards Syndrome 1: 8,000

Trisomy Involves the Addition of a Chromosome to a Diploid Genome Viability in Human Aneuploidy Up to 30 percent of all fertilized eggs in humans may contain an error in chromosome number! 45,X has one of the highest incidence rates among abortuses. Also, about 80 percent of 45,X have the maternal X.

Polyploidy, in Which More Than Two Haploid Sets of Chromosomes Are Present, Is Prevalent in Plants

Figure 8-9 Copyright © 2006 Pearson Prentice Hall, Inc.

Polyploidy, in Which More Than Two Haploid Sets of Chromosomes Are Present, Is Prevalent in Plants Autopolyploidy

Figure 8-10 Copyright © 2006 Pearson Prentice Hall, Inc.

Polyploidy, in Which More Than Two Haploid Sets of Chromosomes Are Present, Is Prevalent in Plants Allopolyploidy

Endopolyploidy

Variation Occurs in the Structure and Arrangement of Chromosomes

Figure 8-14 Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-14a Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-14b Copyright © 2006 Pearson Prentice Hall, Inc.

Gene Xeroxing Gene Copy Number Variants

Figure 8-14c Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-14d Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-14e Copyright © 2006 Pearson Prentice Hall, Inc.

A Deletion Is a Missing Region of a Chromosome

Figure 8-15 Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-15a Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-15b Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-15c Copyright © 2006 Pearson Prentice Hall, Inc.

Table 8-2 Copyright © 2006 Pearson Prentice Hall, Inc.

A Duplication Is a Repeated Segment of the Genetic Material

Figure 8-17 Copyright © 2006 Pearson Prentice Hall, Inc.

A Duplication Is a Repeated Segment of the Genetic Material Gene Redundancy and Amplification: Ribosomal RNA Genes The Bar-Eye Mutation in Drosophila

Figure 8-18a Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-18b Copyright © 2006 Pearson Prentice Hall, Inc.

A Duplication Is a Repeated Segment of the Genetic Material The Role of Gene Duplication in Evolution

Inversions Rearrange the Linear Gene Sequence

Figure 8-19 Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-20 Copyright © 2006 Pearson Prentice Hall, Inc.

Inversions Rearrange the Linear Gene Sequence Consequences of Inversions during Gamete Formation

Figure 8-21 Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-22a Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-22b Copyright © 2006 Pearson Prentice Hall, Inc.

Inversions Rearrange the Linear Gene Sequence Position Effects of Inversions Evolutionary Advantages of Inversions

Translocations Alter the Location of Chromosomal Segments in the Genome

Figure 8-23 Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-23a Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-23b Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-23c Copyright © 2006 Pearson Prentice Hall, Inc.

Translocations Alter the Location of Chromosomal Segments in the Genome Translocations in Humans: Familial Down Syndrome

Figure 8-24 Copyright © 2006 Pearson Prentice Hall, Inc.

Figure 8-25 Copyright © 2006 Pearson Prentice Hall, Inc.

Fragile Sites in Humans Are Susceptible to Chromosome Breakage Fragile X Syndrome (Martin–Bell Syndrome)

Figure 8-26 Copyright © 2006 Pearson Prentice Hall, Inc.