第九章染色体畸变(修改)

1、GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNC

2、ZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENE

3、TICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS第九章 染色体畸变Chromosome AberrationGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GE

4、NETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCG

5、ENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS基本概念染色体畸变指染色体的结构或数目发生了异常的变化。染色体畸变可能是自发的，也可通过化学物质或放射线处理而诱发；染色体结构变异包括缺失、重复、倒位、易位四类；一对同源染色体存在相同的结构改变称结构纯合体，若仅其中一条染色体结构发生改变叫结构杂合体；染色体数的改变分为两类，一类是整倍体，另一类是非

6、整倍体；整倍体是增加或减少整套的染色体，非整倍体是增加或减少一条或几条染色体；GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZ

7、HJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS

8、ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.1 染色体结构变异染色体结构变异可分为四种类型。缺失(deletion)：失去了部分染色体片段；重复(duplication)：增加部分染色体片段；倒位(inversion)：染色体片段作180的颠倒再重接在染色体上；易位(translocation)：两条非同源染色体之间发生部分片段的交换。一对同源染色体其中一条是正常的而另一条发生了结构变异，含有这类染色体的个体或细胞称为结构杂合体(stru

9、ctural heterozygote)。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENET

10、ICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJN

11、CZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.1.1 缺失(deletion) 6.1.1.1 缺失的类型 1)、末端缺失(terminal deletion) 末端发生缺失。由于丢失了端粒，故一般很不稳定。 2)、中间缺失(interstitial deletion) 染色体中部缺失了一个片段。这种缺失较为稳定，故较常见。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETI

12、CS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENE

13、TICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSABCFDEGHNormalAFD

14、EGHBCFDEGHInterstitialTerminalGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENE

15、TICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENE

16、TICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.1.1.2 缺失的细胞学和遗传学效应1)、在减数分裂同源染色体配对时，缺失杂合体出现特征性的环状结构缺失环(deletion loop)。2)、致死或出现异常。如人类的猫叫综合症(cat cry syndrome)是由于第5号染色体短臂缺失所致。12312377456deletion loopNormal chromotidsDeletion chromotidsGENETICS ZHJNCGENETICS ZH

17、JNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGEN

18、ETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNC

19、ZHJNCZHJNC GENETICSGENETICSGENETICS3)、假显性(pesudo-dominance) 如果缺失的部分包括某些显性基因，那么同源染色体上与这一缺失相对位置上的隐性基因就得以表现，这一现象称为假显性。如果蝇的缺刻翅遗传。 +Nw红眼缺刻翅X+XN白眼正常翅XwY+w红眼正常+红眼正常wN白眼缺刻N死亡GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJN

20、CZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GEN

21、ETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.2.2 重复(duplication)6.2.2.1 重复的类型1)、顺接重复(tandem duplication) 重复片段与原有片段毗邻且

22、方向相同。2)、反接重复(reverse duplication) 重复片段与原有片段毗邻但方向相反。3)、异位重复(displaced duplication) 重复片段位于染色体其它位置或其它染色体上。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENE

23、TICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGE

24、NETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSABCFDEGHBCFADEGHBCCBFADEGHBCABCFDEGHBCNormalTandemReverseDisplacedGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNC

25、GENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJN

26、C GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.2.2.2 重复的

27、细胞学和遗传学效应1)、染色体重复与正常染色体联会时，在粗线期的染色体上会出现环状突起。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZ

28、HJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENE

29、TICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS2)、位置效应(position effect) 一个基因随着染色体畸变而改变它和邻近基因的位置关系，从而改变了表型的现象称位置效应。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJN

30、CZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJN

31、C GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS 3)、剂量效应(dosage effect) 如在细胞或个体中既有重复又有缺失，总的基因组平衡的话，除染色体重排引起的效应外，个体表型是

32、正常的。但若总量因重复而增加，那么某些基因及其产物的剂量也随之增加，如这些基因或产物十分重要的话必然会引起表型异常。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETI

33、CS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENE

34、TICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.2.3 倒位(inversion)6.2.2.1 倒位的类型1)、臂内倒位(paracentric inversion) 倒位片段不含着丝粒。2)、臂间倒位(pericentric inversion) 倒位片段含着丝粒。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJ

35、NCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZH

36、JNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSABCFDEGAB

37、CFDEGABCFDEGParacentricABCFDEGABCFDEGACBFEDGPericentricGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS

38、ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETIC

39、S ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.2.3.2 倒位的细胞学和遗传学效应1)、产生倒位环(inversion loop)。ABCFDEGABCFDEGParacentricADFGADFGBCBCEEPericentricGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNC

40、ZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGEN

41、ETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSSingle inversionMultiple inver

42、sionGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZ

43、HJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC

44、GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS2)、抑制倒位区内的重组，形成假连锁。不论是臂间倒位还是臂内倒位，由于倒位环内非姐妹染色单体间发生单交换，而交换的产物都带有缺失或重复，不能形成有功能的配子，因而好象被抑制了，或相当程度地减少杂合子中的重组。这种现象称为交换抑制因子(crossover repressor,C)。据Schultz和Redfield(1951)在果蝇中的研究发现，一对染色体的杂合倒位，能增加同一染色体组中的非倒位片段的交换发生。这种现象称为Schultz-Redfield效应。3)、倒位

45、杂合体育性降低，表现部分不育。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGEN

46、ETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNC

47、ZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSParacentricGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETI

48、CS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENET

49、ICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSParacentricGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GE

50、NETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENE

51、TICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSPericentricGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCG

52、ENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC

53、 GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.2.4 易位(tra

54、nslocation)6.2.4.1 易位的类型1)、相互易位(reciprocal translocation) 非同源染色体之间相互置换了一段染色体片段。2)、插入易位(interstitial translocation) 一条染色体片断插入到非同源染色体区段之中。GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETIC

55、SGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJN

56、CZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSABCFDEMNQOPAFDEMNQOPBCInterstitial translocationABCFDEMNQOPABCQOPMNFDEReciprocal translocationGENETICS Z

57、HJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENE

58、TICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETI

59、CSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICS6.2.4.2 易位的细胞学效应 相互易位杂合体在Metaphase I 由于同源部分的紧密配对而出现特征性的十字形图像。 随着分裂的进行，十字形图像逐渐开放形成一个环形或双环状的“8”字形。 到Anaphase I ，染色体表现出不同的分离方式：1) 相邻分离1(adjacent segregation-1)2) 相邻分离2(adjacent segregation-2)3) 交互分离 (alternate segregation)GENETICS ZHJNCGENETICS ZHJNCGEN

60、ETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSGENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNC GENETICS ZHJNCGENETICS ZHJNCGENETICS ZHJNCZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSZHJNCZHJNCZHJNC GENETICSGENETICSGENETICSG