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1、Xunchao Xiang Southwest University of Science and Technology Chapter 7 Chapter 7 Chromosome Mutations: Variation in Chromosome Mutations: Variation in Number and ArrangementNumber and Arrangementn n7.1 Variation in Chromosome Number: An Overview7.1 Variation in Chromosome Number: An Overviewn n7.2 N
2、onjunction: The Origin of Aneuploidy7.2 Nonjunction: The Origin of Aneuploidyn n7.3 Monosomy7.3 Monosomyn n7.4 Trisomy7.4 Trisomyn n7.5 Polyploidy and Its Origins7.5 Polyploidy and Its Originsn n7.6 Variation in Chromosome Structure and Arrangement: An 7.6 Variation in Chromosome Structure and Arran
3、gement: An OverviewOverviewn n7.7 Deletions7.7 Deletionsn n7.8 Duplications7.8 Duplicationsn n7.9 Inversions7.9 Inversionsn n7.10 Translocations7.10 TranslocationsXunchao Xiang Southwest University of Science and Technology 7.1 Variation in Chromosome Number: An 7.1 Variation in Chromosome Number: A
4、n OverviewOverviewn nGenome: the total set of genes contained in a Genome: the total set of genes contained in a haploid of the species constitutes the genome.haploid of the species constitutes the genome.n nThe all chromosomal number of a gamete The all chromosomal number of a gamete produced from
5、diploid is designated as produced from diploid is designated as basic basic chromosome numberchromosome number 染色体基数染色体基数染色体基数染色体基数, , and make and make up a single complete set (up a single complete set (x) x) . .n nMonoploid (Monoploid (x x) )一倍体一倍体: : individual, which has only individual, which
6、has only one set of chromosomes.one set of chromosomes.n nHaploid(Haploid(单倍体单倍体): individual only with gametic ): individual only with gametic chromosomes.chromosomes.n nIts all chromosomal number is indicated as Its all chromosomal number is indicated as n. n.Xunchao Xiang Southwest University of
7、Science and Technology1. 单倍体的产生 (1) (1)自然产生：由单性生殖产生自然产生：由单性生殖产生未受精的雌、雄配子，甚至助细胞、反细胞等直接发育形成单倍体胚。 部分动物，如膜翅目昆虫(蜂、蚊)和某些同翅目昆虫(白蚁)的雄性个体都是孤雌生殖形成的自然单倍体。(2) (2) 人工获得单倍体人工获得单倍体花药培养花药培养：花药离体培养诱导配子体(花粉或子房)发育形成单倍体植株 这是应用最为广泛、成功的人工方法种间或属间远缘杂交种间或属间远缘杂交 栽培大麦(Hordeum vudare, 2n=2x=14)与野生球茎大麦(H. bulbosus, 2n=2x=14)杂种胚
8、发育过程中，两物种染色体的行为不协调可导致球茎大麦的染色体逐渐丢失(称为染色体消减现象)，可获得大麦的单倍体植株Xunchao Xiang Southwest University of Science and Technology花药培养获得单倍体染色体消减获得单倍体大麦Xunchao Xiang Southwest University of Science and Technology2. 单倍体在遗传育种研究的应用(1)提高育种的选择效率、加速育种进程 基因成单，加倍，纯合体(2)作为良好的遗传研究材料 基因成单，每个基因都发挥作用(3)用以分析染色体组间同源关系 部分同源关系Xunc
9、hao Xiang Southwest University of Science and Technology 7.1 Variation in Chromosome Number: An 7.1 Variation in Chromosome Number: An OverviewOverviewn nEuploid(整倍体): an individual that has complete sets of chromosomes present.n nAneuploid (非整倍体): an individual gains or loses one or more chromosome
10、s, but not a complete set.n nPolyploid (多倍体): an individual with more than two complete sets chromosomes present.Xunchao Xiang Southwest University of Science and Technology 7.1 Variation in Chromosome Number: An 7.1 Variation in Chromosome Number: An OverviewOverviewn nTerminology for Variation in
11、Chromosome NumbersTerminology for Variation in Chromosome Numbersn nTerm ExplanationTerm Explanationn nDisomic (normal) 2Disomic (normal) 2n nn nAneuploid 2Aneuploid 2n n x x chromosomes chromosomesn n Monosomic 2 Monosomic 2n n1 1n n Double Monosomic 2 Double Monosomic 2n n1 11 1n n Nullisomic 2 Nu
12、llisomic 2n n2 2n n Trisomic 2 Trisomic 2n n1 1n n Double Trisomic 2 Double Trisomic 2n n1 11 1n n Tetrasomic, pentasomic, etc. 2 Tetrasomic, pentasomic, etc. 2n n 2, 22, 2n n 3, etc.3, etc.n nEuploid Multiples of Euploid Multiples of n nn n Diploid 2 Diploid 2n nn n Polyploid 3 Polyploid 3n n,4,4n
13、n,5,5n n, , Xunchao Xiang Southwest University of Science and TechnologyPolyploidyn nTerm Explanationn nTriploid(三倍体) 3nn nTetraploid (四倍体) 4n n nPentaploid (五倍体) 5nn nAutoploid (同源多倍体) Multiples of the same genomen nAllopolyploid (异源多倍体) n n(Amphidiploid)Multiples of different Multiples of differen
14、t genomesgenomesXunchao Xiang Southwest University of Science and TechnologyCharacteristics of polyploidCharacteristics of polyploidn n(1). Polyploid often increases plant size (included cell, organelle etc.).Xunchao Xiang Southwest University of Science and TechnologyCharacteristics of polyploidCha
15、racteristics of polyploidn n(2) Polyploid often increases plant vigor (heterosis).n n(3). Fertility of gametes are often reduced, even infertile completely.Xunchao Xiang Southwest University of Science and TechnologyHypoploid and HyperploidHypoploid and Hyperploidn nHypoploid (Hypoploid (亚倍体亚倍体) )：
16、the individual that its the individual that its chromosome number is loss than diploid.chromosome number is loss than diploid.n nFor example, monosomic, double monosomic, For example, monosomic, double monosomic, nullisomic, etc.nullisomic, etc.n nHyperploid (Hyperploid (超倍体超倍体) )： the individual th
17、at its the individual that its chromosome number is more than diploid.chromosome number is more than diploid.n nFor example, trisomic, tetrasomic, etc. For example, trisomic, tetrasomic, etc. Xunchao Xiang Southwest University of Science and Technology7.2 Nonjunction: The Origin of Aneuploidy7.2 Non
18、junction: The Origin of AneuploidyXunchao Xiang Southwest University of Science and Technology7.3 Monosomy(7.3 Monosomy(单体性单体性单体性单体性) )n nMonosomy: The loss of one chromosome in a Monosomy: The loss of one chromosome in a normal diploid produces a (2n normal diploid produces a (2n 1) complement 1) c
19、omplement and is called monosomy or monosomic.and is called monosomy or monosomic.n nFor example, TFor example, Turner syndrome(45, XO).urner syndrome(45, XO).Xunchao Xiang Southwest University of Science and Technology7.3 Monosomy7.3 Monosomyn nCri-du-Chat Syndrome(Cri-du-Chat Syndrome(猫叫综合症猫叫综合症)
20、)n nThis syndrome is associated with the loss of part This syndrome is associated with the loss of part of the short arm of chromosome 5, strictly, this of the short arm of chromosome 5, strictly, this case should be referred to as segmental deletion. case should be referred to as segmental deletion
21、. n nIts genetic constitution may be designated as 46, Its genetic constitution may be designated as 46, 5p5p, meaning that such an individual has all 46 , meaning that such an individual has all 46 chromosomes but that some of the chromosomes but that some of the p p arm of one arm of one member of
22、 the chromosome 5 pair is missing. member of the chromosome 5 pair is missing. n nIncidence: 1/50,000 live births.Incidence: 1/50,000 live births.Xunchao Xiang Southwest University of Science and TechnologyCri-du-Chat SyndromeCri-du-Chat SyndromeXunchao Xiang Southwest University of Science and Tech
23、nology7.4 Trisomy(7.4 Trisomy(三体性三体性三体性三体性) )n nThe addition of an extra chromosome products The addition of an extra chromosome products somewhat more viable individuals in both animal somewhat more viable individuals in both animal and plant species than does the loss of a and plant species than d
24、oes the loss of a chromosome.chromosome.n nDown SyndromeDown Syndromen nIt is the only human autosomal trisomy in which It is the only human autosomal trisomy in which a significant number of individuals survive longer a significant number of individuals survive longer than a year past birth. It res
25、ults from trisomy of than a year past birth. It results from trisomy of chromosome 21, and is also called simply chromosome 21, and is also called simply trisomy 21(is designated 47, 21trisomy 21(is designated 47, 21) )n nIncidence: 1/800 live birth.Incidence: 1/800 live birth.Xunchao Xiang Southwes
26、t University of Science and TechnologyDown SyndromeDown SyndromeXunchao Xiang Southwest University of Science and TechnologyDown SyndromeDown SyndromeXunchao Xiang Southwest University of Science and Technology Viability in Human Aneuploid Conditions Viability in Human Aneuploid Conditionsn nPatau S
27、yndrome ( 47,13 )Edwards syndrome (47, 18 )They result in severe malformations and early lethality.Xunchao Xiang Southwest University of Science and Technology Viability in Human Aneuploid Conditions Viability in Human Aneuploid Conditionsn nAt least 1520 percent of all conceptions At least 1520 per
28、cent of all conceptions terminate in spontaneous abortion. About 30 terminate in spontaneous abortion. About 30 percent of all spontaneously aborted fetuses percent of all spontaneously aborted fetuses demonstrate some form of chromosomal demonstrate some form of chromosomal anomaly, and approximate
29、ly 90 percent of all anomaly, and approximately 90 percent of all chromosomal anomalies are terminated prior to chromosomal anomalies are terminated prior to birth as a result of spontaneous abortion.birth as a result of spontaneous abortion.n nA large percentage of those demonstrating A large perce
30、ntage of those demonstrating chromosomal abnormalities are aneuploids. The chromosomal abnormalities are aneuploids. The aneuploid with highest incidence among aneuploid with highest incidence among abortuses is the 45,X condition.abortuses is the 45,X condition.Xunchao Xiang Southwest University of
31、 Science and Technology7.5 Polyploidy and Its Origins7.5 Polyploidy and Its OriginsXunchao Xiang Southwest University of Science and Technology7.5 Polyploidy and Its Origins7.5 Polyploidy and Its Originsn n1. Origin of polyploidy1. Origin of polyploidyn nPolyploid originates in two ways:Polyploid or
32、iginates in two ways:n n(1) Autopolyploid: the addition of one or more (1) Autopolyploid: the addition of one or more extra sets of chromosomes, identical to the extra sets of chromosomes, identical to the normal haploid complement of the same normal haploid complement of the same species.species.n
33、n(2) Allopolyploidy(2) Allopolyploidy(异源多倍体异源多倍体): the addition of one ): the addition of one or more extra sets of chromosomes, different to or more extra sets of chromosomes, different to the normal haploid complement of the same the normal haploid complement of the same species.species.Xunchao Xi
34、ang Southwest University of Science and Technology7.5 Polyploidy and Its Origins7.5 Polyploidy and Its OriginsAmphidiploidXunchao Xiang Southwest University of Science and TechnologyAutopolyploid(Autopolyploid(同源多倍体同源多倍体同源多倍体同源多倍体) )Having being replicated, do not appearXunchao Xiang Southwest Unive
35、rsity of Science and TechnologyAllopolyploidy(Allopolyploidy(异源多倍体异源多倍体异源多倍体异源多倍体) )Xunchao Xiang Southwest University of Science and Technology2. 多倍体的形成途径及其应用(1)未减数配子结合减数分裂(2)体细胞染色体数加倍有丝分裂(3)人工诱导多倍体的应用Xunchao Xiang Southwest University of Science and Technology(1)未减数配子结合桃树(2n=2x=16=8)的未减数配子(n=2x=16
36、)融合形成同源多倍体l未减数配子未减数配子 四倍体(2n=4x=32=8)l未减数配子正常配子 三倍体(2n=3x=24=8)Xunchao Xiang Southwest University of Science and Technology(1)未减数配子结合种间杂种F1未减数配子融合形成异源多倍体例：Xunchao Xiang Southwest University of Science and Technology(2)体细胞染色体数加倍体细胞染色体加倍的方法l最常用的方法：秋水仙素处理分生组织阻碍有丝分裂细胞纺锤丝(体)的形成处理浓度：0.01-0.4%(0.2%)处理时间：视材
37、料而定间歇处理效果更好同源多倍体的诱导l诱导二倍体物种染色体加倍同源多倍体(偶倍数)异源多倍体的诱导l诱导杂种F1染色体加倍双二倍体l诱导二倍体物种染色体加倍同源多倍体杂交双二倍体Xunchao Xiang Southwest University of Science and Technology(3)人工诱导多倍体的应用1.克服远缘杂交的不孕性2.克服远缘杂种的不实性3.创造种间杂交育种的中间亲本 实质是克服远缘杂交不育性4. 人工合成新物种、育成作物新类型人工合成同源多倍体方法：直接加倍例：同源四倍体芥麦、同源三倍体甜菜人工合成异源多倍体方法：物种间杂交杂种F1染色体数目加倍实例：八倍体
38、小黑麦(图示) 、六倍体小黑麦(图示)Xunchao Xiang Southwest University of Science and Technology八倍体小黑麦的人工合成与应用Xunchao Xiang Southwest University of Science and Technology六倍体小黑麦的人工合成与应用Xunchao Xiang Southwest University of Science and Technology7.6 Variation in Chromosome Structure and 7.6 Variation in Chromosome Str
39、ucture and Arrangement: An OverviewArrangement: An Overviewn nThe second general class of chromosome The second general class of chromosome aberrations includes structural changes that aberrations includes structural changes that delete, add, or rearrange substantial portions of delete, add, or rear
40、range substantial portions of one or more chromosomes.one or more chromosomes.n nIncluded in this category are Included in this category are deletions and and duplications of genes or part of a of genes or part of a chromosome and rearrangements of genetic chromosome and rearrangements of genetic ma
41、terial in which a chromosome segment of a material in which a chromosome segment of a nonhomlogous chromosome, or merely , or merely transferred to another chromosome.transferred to another chromosome.Xunchao Xiang Southwest University of Science and Technology染色体结构变异结构变异的形成：断裂结构变异的形成：断裂重接重接使染色体产生折断
42、的因素：自然：温度剧变、营养生理条件异常、遗传因素等；人为：物理射线与化学药剂处理等。v染色体折断的结果：正确重接：重新愈合，恢复原状；错误重接：产生结构变异；保持断头：产生结构变异。v结构变异的基本类型：缺失缺失、重复重复、倒位倒位、易位易位。形成、类型与特点；细胞学特征与鉴定；遗传效应。Xunchao Xiang Southwest University of Science and Technology7.7 Deletions(7.7 Deletions(缺失缺失缺失缺失) )n nDeletion: when a chromosome breaks in one or more De
43、letion: when a chromosome breaks in one or more places and a portion of it is lost, the missing piece is places and a portion of it is lost, the missing piece is called a deletion (or a deficiency)called a deletion (or a deficiency)DeletionTerminal deletion ( (顶端缺失顶端缺失顶端缺失顶端缺失) )Intercalary deletion
44、 ( (中间缺失中间缺失中间缺失中间缺失) )Xunchao Xiang Southwest University of Science and Technology7.7 Deletions7.7 DeletionsXunchao Xiang Southwest University of Science and Technology7.7 Deletions7.7 DeletionsTerminal deletionIntercalary deletionXunchao Xiang Southwest University of Science and Technology断裂断裂断裂断裂
45、融合融合融合融合桥桥桥桥顶端缺失的形成顶端缺失的形成( (断裂断裂) )复制复制姊妹染色单体顶端断姊妹染色单体顶端断头连接头连接( (融合融合) )有丝分裂后期有丝分裂后期 ( (桥桥) )新的断裂新的断裂Xunchao Xiang Southwest University of Science and Technology缺失的细胞学鉴定v无着丝粒断片无着丝粒断片：最初发生缺失的细胞在分裂时可见无着丝粒断片。v缺失环缺失环( (环形或瘤形突出环形或瘤形突出) )：中间缺失杂合体偶线期和粗线期出现；v二价体末端突出二价体末端突出：顶端缺失杂合体粗线期、双线期，交叉未完全端化的二价体末端不等长。
46、缺失染色体的联会Xunchao Xiang Southwest University of Science and Technology缺失的遗传效应v缺失区段上基因丢失导致：基因所决定、控制的生物功能丧失或异常；基因间相互作用关系破坏；基因排列位置关系改变。v影响缺失对生物个体危害程度的因素：缺失区段的大小；缺失区段所含基因的多少；缺失基因的重要程度；染色体倍性水平。v缺失纯合体：致死或半致死。v缺失杂合体：缺失区段较长时，生活力差、配子(尤其是花粉)败育或竞争不过正常配子；缺失区段较小时，可能会造成假显性现象假显性现象或其它异常现象(猫叫综合症)。Xunchao Xiang Southwe
47、st University of Science and Technology猫叫综合症 第5号染色体缺失（短臂缺失）患儿发出咪咪声，耳位低下，智商仅2040.Xunchao Xiang Southwest University of Science and TechnologyRobert Horry，七枚，七枚NBA季季后赛总冠军戒指，并且是后赛总冠军戒指，并且是NBA历史上投中三分球总数历史上投中三分球总数第一。第一。“关键先生关键先生”的名号的名号享誉联盟。享誉联盟。2011年年6月月13日，他日，他17岁的女儿阿什利岁的女儿阿什利-霍霍里，因为一种罕见的基因疾病于美国当里，因为一种罕
48、见的基因疾病于美国当地时间周二去世。这疾病被称做地时间周二去世。这疾病被称做“1p36缺失综合征缺失综合征”，一一种神经性并发症种神经性并发症大脑神经瘫痪，大脑神经瘫痪，有着非常严重的呼吸衰有着非常严重的呼吸衰竭疾病，并有多种并发症。竭疾病，并有多种并发症。News title:Daughter Of Robert Horry Passes Away At 17.Her disorder became known as the 1p36 deletion syndrome. It is caused when a child is born missing a part of chromoso
49、me No. 11p36 deletion syndromeXunchao Xiang Southwest University of Science and Technology缺失杂合体的假显性现象Xunchao Xiang Southwest University of Science and Technology7.8 Duplications(7.8 Duplications(重复重复重复重复) )n nDuplication: when any part of the genetic Duplication: when any part of the genetic materia
50、l material a single locus or a large piece of a a single locus or a large piece of a chromosome chromosome is present more than once in the is present more than once in the genome, it is called a duplication.genome, it is called a duplication.Xunchao Xiang Southwest University of Science and Technol
51、ogy7.8 DuplicationsDuplicationDuplicationTandem duplication (顺接重复)Reverse duplication (反接重复)Xunchao Xiang Southwest University of Science and Technology7.8 Duplicationsn nGene Redundancy (Gene Redundancy (基因冗余基因冗余)and Amplification )and Amplification Ribosomal RNA Genes Ribosomal RNA Genesn nGene Re
52、dundancy: A product is coded by Gene Redundancy: A product is coded by multiple copies of genes.multiple copies of genes.n nGene Amplification: the process by which gene Gene Amplification: the process by which gene sequences are selected and differentially sequences are selected and differentially
53、replicated either extrachromosomally or replicated either extrachromosomally or intrachromosomally.intrachromosomally.Xunchao Xiang Southwest University of Science and Technology7.8 Duplications7.8 Duplicationsn nThe Bar Mutation in DrosophilaBar eyeOval eyeXunchao Xiang Southwest University of Scie
54、nce and Technology重复的细胞学鉴定重复圈重复圈( (环环) )果蝇果蝇X X染色体上染色体上16A16A区段重复的形成区段重复的形成Xunchao Xiang Southwest University of Science and TechnologyThe genetic effects of duplicationThe genetic effects of duplicationn n(1). Dosage effectn果蝇眼色遗传的剂量效应，红色(V+)对朱红(V)为显性；n杂合体(V+V)表现为红色；n但(V+VV)的表现型却为朱红色。n说明说明2 2个隐性基因的
55、作用已经超过自己的显性等个隐性基因的作用已经超过自己的显性等位基因，改变了原来的一个隐性基因与一个显位基因，改变了原来的一个隐性基因与一个显性基因的平衡关系。性基因的平衡关系。n n(2). Position effect(2). Position effectXunchao Xiang Southwest University of Science and Technology7.9 Inversions(7.9 Inversions(倒位倒位倒位倒位) )n nInversion: is a type of chromosomal aberration in Inversion: is a
56、 type of chromosomal aberration in which a segment of a chromosome is turned which a segment of a chromosome is turned around 180within a chromosome.around 180within a chromosome.InversionParacentric inversion ( (臂内倒位臂内倒位臂内倒位臂内倒位) )Pericentric inversion ( (臂间倒位臂间倒位臂间倒位臂间倒位) )Xunchao Xiang Southwest
57、University of Science and TechnologyPericentric inversionXunchao Xiang Southwest University of Science and Technology Consequences of Inversions During Consequences of Inversions During Gamete FormationGamete Formationn nInversion heterozygotes: organisms with one inverted chromosome and one noinver
58、ted homolog.n nWhen pairing between inversion heterozygotes in meiosis is accomplished only if they form an inversion loop. n nIf crossing over occurs within the inversion loop:Xunchao Xiang Southwest University of Science and TechnologyParacentric inversion heterozygoteParacentric inversion heteroz
59、ygoteNormalInvertedXunchao Xiang Southwest University of Science and TechnologyParacentric inversion heterozygoteParacentric inversion heterozygoteNormalInvertedXunchao Xiang Southwest University of Science and TechnologyParacentric inversion heterozygoteParacentric inversion heterozygoten nAnaphase
60、 Anaphase bridgesbridges Xunchao Xiang Southwest University of Science and TechnologyPericentric Inversion HeterozygotePericentric Inversion HeterozygoteNormalInvertedXunchao Xiang Southwest University of Science and TechnologyPericentric Inversion HeterozygotePericentric Inversion HeterozygoteXunch
61、ao Xiang Southwest University of Science and TechnologyGenetic Effects of InversionGenetic Effects of Inversionn n(1). Partial sterility of inversion heterozygote.(1). Partial sterility of inversion heterozygote.n nReasons: producing of deletion or duplication Reasons: producing of deletion or dupli
62、cation gametes.gametes.n n(2). Original arrangement sequence of genes in (2). Original arrangement sequence of genes in chromosome is changed.chromosome is changed.n nDistance between genes is changed; Position Distance between genes is changed; Position effect probably takes place; Values of crossi
63、ng effect probably takes place; Values of crossing over between genes in inversion heterozygote over between genes in inversion heterozygote reduced.reduced.n n(3). Inversion is one of important factors in (3). Inversion is one of important factors in evolution of organism.evolution of organism.Xunc
64、hao Xiang Southwest University of Science and Technology7.10 Translocations(7.10 Translocations(异位异位异位异位) )n nTranslocation: is the movement of a chromosomal Translocation: is the movement of a chromosomal segment to a new location of segment to a new location of nonhomologousnonhomologous chromosom
65、echromosome in the genome. in the genome.TranslocationSimple translocation ( (简单异位简单异位简单异位简单异位) )Reciprocal translocation ( (相互异位相互异位相互异位相互异位) )Xunchao Xiang Southwest University of Science and TechnologySimple translocationXunchao Xiang Southwest University of Science and TechnologyReciprocal trans
66、locationXunchao Xiang Southwest University of Science and TechnologyReciprocal translocationXunchao Xiang Southwest University of Science and TechnologyReciprocal translocationCrosslike configuration(十字结构)Evidence in identifying of cytologyXunchao Xiang Southwest University of Science and Technology
67、Reciprocal translocationAlternate(交替式交替式)Adjacent(邻近式邻近式)Xunchao Xiang Southwest University of Science and TechnologySynapsis and segregation of translocation Synapsis and segregation of translocation heterozygoteheterozygoteNormalBalancedD,DD,DAlternateAdjacentXunchao Xiang Southwest University of
68、Science and TechnologySegregation of translocation heterozygoteSegregation of translocation heterozygoten nAlternate segregation: to produce normal and balanced gametes.n nAdjacent segregation: to produce duplicate and delete gametes.Xunchao Xiang Southwest University of Science and TechnologyGeneti
69、c effects of translocationGenetic effects of translocationn n(1).Semisterility(半不育性).n n(2). Linkage group of organism is changed by translocation.n n(3). Values of crossing over of genes in translocation heterozygote is reduced.n n(4). Translocation may produce new species and leads to involution.X
70、unchao Xiang Southwest University of Science and TechnologyTranslocation in Humans: Familial Down Translocation in Humans: Familial Down SyndromeSyndromeRobertsonian Translocation45 chromosomesu知 识 点 染色体数目变异概况；非整倍体产生的起源；单体性；三体性；多倍体及其起源；染色体结构变异概况；缺失；重复；倒位；易位。u重 点 整倍体和非整倍体的类型；多倍体的特征及其起源；结构变异的类型及其遗传效应。
71、u难 点 臂内倒位杂合体和相互易位杂合体可能产生的配子类型和育性分析。Highlightsu基本要求n1. 识 记：染色体基数（basic chromosome number ）、一倍体（Monoploid）、单倍体（Haploid）、整倍体（Euploid）、非整倍体（Aneuploid）、多倍体（Polyploid）、单体（Monosomic）、双单体（double monosomic）、缺体（Nullisomic）、三体（Trisomic）、双三体（double trisomic）、二倍体（diploid）、亚倍体（Hypoploid）、超倍体（Hyperploid）、同源多倍体（Aut
72、opolyploid）、异源多倍体（Allopolyploidy）、缺失（deletion）、重复（duplication）、倒位（inversion）、易位（translocation） Highlightsn2. 领 会：非整倍体和多倍体的起源；染色体不同结构变异类型导致的断裂点数目；结构变异杂合体的染色体配对情况。 n3. 简单应用：多倍体的特征；染色体不同结构变异类型的遗传效应。n4. 综合应用：单倍体的产生及其在遗传育种研究中的应用；人工诱导多倍体的应用；臂内倒位杂合体和相互易位杂合体可能产生的配子类型和育性分析。 Highlightsu考核要求n1. 本章重点名词的英语词汇；n2. 非整倍体的不同类型并能图示其染色体结构； n3. 多倍体的特征；n4. 染色体不同结构变异类型的遗传效应；n5. 不同结构变异类型的染色体存在的断裂点数目；n6. 哪些染色体结构变异类型的杂合体存在loop结构；n7. 臂内倒位杂合体和相互易位杂合体可能产生的配子类型和育性分析。 Highlights
