人類染色體核型分析

1、人類染色體核型分析核型分析染色體型態(tài) Chromosome morphology染色體異常 Chromosome abnormal核型分析 Karyotype analysis染色體的組成Chromatin 染色質(zhì)Chromatin is the DNA-containing substance extractable from eukaryotic nuclei Chromatin is NOT a macromolecule, thus has no fixed composition染色質(zhì)的特性染色反應Isopyconosis without differentiationHeterop

2、yconosis with differentiationPositively (tightly coiled) v.s. negative (loosely coiled)Euchromatin v.s. HeterochromatinEuchromatin loose structure genetically activeHeterochromatinCompact structure genetically silentHeterochromatinConstitutive v.s. facultativeChromomere 染色粒Compact form of nucleosome

3、NucleosomeBasic structure unit of chromosomeNucleosome structureSupercoiledLinear differentiationDifferent degree of coilingTelomereCentromereChromomereNucleolar organizerTelomereTelomereCentromereKinetochoreSpindle fiber attachmentFirst constrictionChromosome typeMetacentricSubmetacentricAcrocentri

4、cTelocentricNucleolar organizer 核仁Secondary constrictionThe collecting point of nucleolar material nucleolusProduce 18s and 28s rRNATomato telomereGrasshopper telomereVicia faba chromosomeRye chromomereZea mays Nucleolar organizerChange in chromosome morphologyChromosome break apartReunionUnunitedex

5、changedExchangeChromosome arm rearrangementTranslocationBetween the arms of different chromosomesTranslocationCentric fusionChromosome number variationEuploidyAneuploidyEuploidytypesymbolSet of chromosomemonoploidnABCDiploid2nAABBCCPolyploidTriploid3nAAABBBCCCTetraploid4nAAAABBBBCCCCPentaploid5nAAAA

6、ABBBBBCCCCCEuploidyAllopolyploidySets of chromosome came from different speciesAutopolyploidySets of chromosome came from same speciesSpecies A2n=AASpecies B2n=BBSpecies C2n=CCAutotriploid3n=AAAAutotetraploid4n=AAAAAutohexaploid6n=AAAAAAAutopetaploid5n=AAAAAF12n=ABAllotetraploid4n=AABBTriploid3n=ABB

7、Autoallohexaploid6n=AABBBBAutoallooctaploid8n=AAAABBBBTriploid3n=ABCAllohexaploid6n=AABBCCAneuploidtypesymbolNumber of chromosomeDisomic2nAABBCCmonosomic2n-1AABBCNullisomic2n-2AABBPolysomicTrisomic2n+1AABBCCCDouble trisomic2n+1+1AABBBCCCTetrasomic2n+2AABBCCCCPentasomic2n+3AABBCCCCCHuman chromosomeCh

8、romosome number 46Male 44 + XYFemale 44+ XX1956 Tjio & LevanQ-banding: fluorescenceC-Banding: Giemsa stainG-BandingR-BandingHuman and rat karyotypesRules for arranging chromosomeFrom Long to shortIf same in lengthMetacentric chromosomeSubmetacentric chromosomeAcrocentric chromosomeTelocentric chromosomeKaryotype analysisGet a photo of chromosomesCut off each chromosomePairing the homologous chromosomeDraw a base line in a piece of paperArrange the chromosome according to the rules shown in previous pageMeasure each arms of the chromosome pairCalculate the