Chapter 10 Inheritance analysis of chromosome aberration

1. Chapter 10 Inheritance analysis of chromosome aberration • Variation in chromosome structure • Deletions • Duplication • Inversions • Translocations • Variation in chromosome number • Euploid • Aneuploid

2. 第十章 染色体畸变的遗传分析 • 染色体结构变异 • 缺失 • 重复 • 倒位 • 易位 • 染色体数目的变异 • 整倍体 • 非整倍体

3. Characteristics of Drosophila salivary gland chromosomes果蝇唾腺染色体特性 • Magnitude and extensibility • Somatic synapsis • Band and interband • Puff Structure • 巨大性和伸展性 • 体联会 • 横纹结构 Puff结构

4. Variation in chromosome structure—deletions染色体结构变异--缺失 Deficiencies The loss of a segment from a normal chromosome The types of deficiencies Intercalary (deletion)and terminal 染色体丢失了一个片段叫缺失 缺失类型: 中间缺失 末端缺失

5. Formation of Terminal deletion末端缺失的形成

6. Formation of intercalary deletion中间缺失的形成

7. Cytological behavior细胞学效应 A loop is generally observed if the deficiency is long enough and is located an interstitial region 普遍生成一个缺失环

8. Chromosomal synapsis of deficiency缺失染色体联会

9. Deletion loop of Drosophila salivary gland chromosome果蝇唾腺染色体的缺失环

10. Genetic effect of deletion heterozygote缺失杂合子的遗传学效应 Pseudodominant Lethal effect Formation ofring chromosome and breakage-fusion-bridge cycle 假显性 致死效应 形成环状染色体和断裂融合桥循环

11. Pseudodominant effect of deletion heterozygote缺失杂合子的假显性效应

12. Example of deletion in human--Cri-du-Chat Syndrome人类缺失实例--猫叫综合症

13. The karyotype of Cri-du-Chat Syndrome猫叫综合症的核型

14. Variation in chromosome structure--duplicationsAn extra piece of chromosome segment either attached to the same homologous chromosome or transposed to one of the non-homologous members of the genome重复：一个染色体上的某一片段出现两份或两份以上的现象

15. Types of duplications重复的种类 Tandem duplication--串联重复 Reverse tandem duplication--反向串联重复

16. Formation of duplication重复的形成

17. Non-equal cross-over of homogenous chromosome同源染色体的不等交换

18. Cytological behavior of duplication heterozygote重复杂合体的细胞学行为 Duplication loop 重复环

19. Genetic effect of duplication heterozygote重复杂合子的遗传效应 Dosage effect Position effect Lethal effect 剂量效应 位置效应 致死效应

20. The Bar mutation in Drosophila果蝇的棒眼突变

21. The duplication at 16A of X chromosome in Drosophila果蝇X染色体在16A的重复

22. Position effect位置效应

23. Variation in chromosome structure--inversions A change in linear sequence of the genes in a chromosome which results in the reverse order of genes in a chromosome segment 倒位：染色体上某一片段发生颠倒，造成染色体上基因顺序重排的现象

24. Types of inversions--倒位的种类 Based on the position of two breaks of an inversion in relation to the kinetochore of a chromosome, inversion are of two types: Paracentric inversion：both breaks occur in the same arm so the inverted region does not include a kinetochore. Pericentric inversion：the two breaks occur in opposite arms of a chromosome. Dicentric bridges and acentric fragments at anaphase-I and –II are not observed in pericentric inversion 臂内倒位：倒位出现在同一臂内，因此倒位不包括着丝粒 臂间倒位：倒位发生在一条染色体的两条臂上

25. Formation of inversion--倒位的形成

26. Cytological behavior--pericentric inversion细胞学行为--臂间倒位 A loop is usually observed in a heterozygous inversion at pachynema 在粗线期，倒位杂合子会出现一个倒位环

27. Cytological behavior--paracentric inversion细胞学行为--臂内倒位 At pachynema, a loop is usually observed in a heterozygous inversion At anaphase-I or –II, chromatin bridge and acentric fragment may be found 在粗线期，倒位杂合子会出现一个倒位环 在后期 I或Ⅱ，可能出现染色体桥梁和无着丝粒片段

28. Association of inversion heterozygote倒位杂合子的联会

29. Cross-over of pericentric inversion heterozygotes臂间倒位杂合子的交换

30. Cross-over of paracentric inversion heterozygotes臂内倒位杂合子的交换

31. Genetic effect and application遗传效应及应用 1. Changing the linear order of genes in chromosome 2. Influencing the organism evolution 3. The karyotype is varied in pericentric inversion 4. Breakage point can be used a dominant suppressed factor to locate genes in chromosome: crossover repressor to construct balanced lethal system—permanent hybrid 改变基因在染色体上线性排列 影响生物进化 臂间倒位可改变细胞染色体核型 断裂点可用作显性抑制因子对染色体上的基因定位

32. Genetic effect and application

33. Variation in chromosome structure--translocations The movement of a chromosomal segment to a new location in the genome 易位是一个染色体片段转移到基因组中新的位置

34. Types of translocation易位类型 Reciprocal translocation: Involveing the exchange of segments between two non-homologous chromosomes Whole-arm translocation Robertsonian translocation 相互易位：是发生在两个非同源染色体之间的交换。 整臂易位 罗伯逊式易位

35. Origin of translocation易位的来源

36. Cytological behavior细胞学行为 At pachynema in meiosis, translocation heterozygote chromosomes form a cross-shaped configuration 在减数分裂粗线期，染色体易位杂合子形成十字型配置

37. Synapsis and separation of translocation heterozygotes易位杂合体的联会与分离

38. Separation of translocation heterozygotes易位杂合体的分离

39. Genetic effect and application遗传效应及应用 Semi-sterility in diploid species Constructing new karyotypes or linkage groups, resulting in evolution of organism. For example: the evolution of rye Using translocation-gene-linkage technique to gene location Preventing injurious insects Using B-A translocations to study gene effects or gene location or relationship among linkage groups 二倍体物种的半不育 构建新的染色体核型或连锁群，促时进生物进化。例如：黑麦的演变 使用连锁-易位基因技术对基因定位 害虫防治 采用易位方法，研究基因效应或定位基因或研究连锁群之间的关系

40. Application in agricultural production Using translocation technology to construct the autosexing strain in silkworm

41. Translocation in humans: Familial Down Syndrome人类的易位--唐氏综合症家族

42. Variation in chromosome number染色体数目的变异 The type of chromosome number variation Euploid Aneuploid Genome: The basic set of chromosomes in a gamete of diploid organism is called genome, designed as ‘x’ 染色体数目变异的类型 ： 整倍体 非整倍体 基因组： 二倍体生物正常配子中所包含的整套染色体

43. Euploid--整倍体 • Euploid: the organisms those contain only complete haploid sets of chromosome • Monoploid, x2n=x • Diploid, 2x2n=2xn=x • Tripoid, 3x2n=3x • Tetraploid, 4x2n=4xn=2x • For example • Maize： diploid(2n=2x=20, n=x=10) • Rice： diploid(2n=2x=24, n=x=12) • Wheat：sixploid(2n=6x=42, n=3x=21, x=7) • 整倍体：以染色体组为单位，呈成套数目的改变，改变后的数目是整倍改变 • 单倍体, x2n=x • 二倍体, 2x2n=2xn=x • 三倍体, 3x2n=3x • 四倍体, 4x2n=4xn=2x • 例如： • 玉米 ： diploid(2n=2x=20, n=x=10) • 水稻 ： diploid(2n=2x=24, n=x=12) • 小麦： sixploid(2n=6x=42, n=3x=21, x=7)

44. Haploid--单倍体 the organisms contain only a set of chromosomes in a cell, which exhibit the smaller cells, tissues, organs, individuals, and sterility to a degree The haploid (n = 2x) of autotetraploid (2n = 4x) shows a higher fertility • 细胞、组织、器官和生物个体较小，高度不育性 • 同源四倍体(2n=4x)的单倍体(n=2x)育性水平高于其它类型 Application in heredity and breeding单倍体在遗传育种研究的应用 To enhance selection efficiency and speed up the process in plant breeding A key material in genetic research To analyze the homologous relationship between chromosome groups 提高育种的选择效率、加速育种进程 是良好的遗传研究材料 用以分析染色体组间同源关系

45. Polyploid The organisms contain more than two sets of chromosomes Autopolyploidy: The genomes are alike because one basic genome is multiplied. Most of the autopolyploidy in nature are autotriploids and autotetraploids. Alloployploidy: The organisms which have the combination of chromosome sets from different species occurring as a consequence of hybridization 同源多倍体：染色体是相同的，因为一个基本的染色体是成倍增加。自然界中的大多数是同源多倍体同源三倍体和同源四倍体 异源多倍体：是两个或两个以上不同物种杂交，它们的杂种经染色体加倍形成

46. Origin of autotetraploids—同源多倍体的来源 1. Occasionally appearing spontaneously in natural diploid population by non-disjunction 2. Deriving from the progenies of twin seedlings and male sterile 3. Induced from temperature shocks, cell and tissue cultures, irradiations and chemicals (colchicines)

47. Meiosis and gene segregation of Autopolyploids同源多倍体的减数分裂 和基因分裂特点

48. Autotriploids--同源三倍体 Autotriploids (3x, AAA): An individual possessing three basic sets of homologous chromosomes 具有3个基本同源染色体组 Phenotype of autotriploids More vigorous vegetative growth, profuse tillering, gigantic phenotype and high ovule abortion 表型：营养生长旺盛，大量分蘖，巨大表型，高雌配子败育率 Cytological behavior 细胞学行为

49. Morphological characteristics of autotetraploid同源四倍体的形态特征 • Slowing in growth • Exhibiting dark green, large leaves • Reducing the number of tillers • 增长缓慢 • 叶深绿色而大 • 减少分蘖数

50. Amphidiploid--双二倍体 • the allotetraploid that contain the equivalent of genomes derived from two separate species • 双二倍体：是来源于两个不同物种的染色体组杂交形成