ICytogenetics: yintoni, uvavanyo lwenziwa njani kwaye luyintoni

Umxholo

• Yenzelwe ntoni
• Kwenziwa njani

Uvavanyo lwe-cytogenetics lujolise ekuhlalutyeni ii-chromosomes kwaye, ke, zichonge utshintsho lwe-chromosomal ezinxulumene neempawu zeklinikhi yomntu. Olu vavanyo lunokwenziwa nangaliphi na ixesha, kwanaxa ukhulelwe ukujonga utshintsho olunokwenzeka kusana.

I-cytogenetics ivumela ugqirha kunye nesigulana ukuba babe nokujonga ngokubanzi i-genome, sinceda ugqirha ukuba enze uxilongo kunye nokunyanga ngokuthe ngqo, ukuba kukho imfuneko. Olu viwo alufuni lungiselelo kwaye ingqokelela ayithathi xesha lide ukuba yenziwe, nangona kunjalo isiphumo sinokuthatha phakathi kweentsuku ezi-3 ukuya kwezi-10 ukuba zikhutshwe ngokwelebhu.

Yenzelwe ntoni

Uvavanyo lwe-cytogenetics yabantu lungabonakaliswa ukuphanda utshintsho olunokwenzeka lwe-chromosomal, ebantwaneni nasebantwini abadala. Kungenxa yokuba ivavanya i-chromosome, esisakhiwo esenziwe nge-DNA kunye neeproteni ezisasazwa kwiiseli ngababini, zingama-23 amabini. Ukusuka kwikaryogram, ehambelana nenkqubo yombutho we-chromosome ngokweempawu zayo, ezikhutshwa njengesiphumo soviwo, kunokwenzeka ukuba uchonge utshintsho kwii-chromosomes, ezinje:

• Utshintsho lwamanani, ezibonakaliswa ngokwanda okanye ukwehla kwinani lama-chromosomes, anjengoko kwenzeka kwi-Down syndrome, apho ubukho be-chromosomes ezintathu ezingama-21 buqinisekiswa, nomntu onee-chromosomes ezingama-47 zizonke;
• Utshintsho kulwakhiwo, apho kutshintshwa, ukutshintshiselana okanye ukupheliswa kommandla othile we-chromosome, njenge-Cri-du-Chat syndrome, ebonakaliswa kukususwa kwenxalenye ye-chromosome 5.

Ke, kunokucelwa ukuba uncede ekuchongeni ezinye iintlobo zomhlaza, ikakhulu ii-leukemias, kunye nezifo zemfuza ezibonakaliswa lutshintsho kulwakhiwo okanye ngokunyuka okanye ukwehla kwenani lama-chromosomes, njenge-Down syndrome, iPatau syndrome kunye neCri-du -Chat, eyaziwa ngokuba yi-meow syndrome okanye ukukhala kwekati.

Kwenziwa njani

Uvavanyo luhlala luqhutywa kwisampulu yegazi. Kwimeko yovavanyo lwabasetyhini abakhulelweyo abanenjongo yokuvavanya iichromosomes ezingekazalwa, kuqokelelwa i-amniotic fluid okanye isixa esincinci segazi. Emva kokuqokelela izinto zebhayoloji kwaye uzithumele elebhu, iiseli ziya kulungiswa ukuze zande kwaye emva koko kongezwe isithinteli sokwahlulwa kweseli, esenza i-chromosome ikwimo yayo ejijekileyo kwaye ijongwe kakuhle.

Ngokuxhomekeka kwinjongo yoviwo, iindlela ezahlukeneyo zemolekyuli zinokusetyenziswa ukufumana ulwazi malunga nekaryotype yomntu, esona sisetyenziswa kakhulu:

• Ibhendi G: yindlela esetyenziswa kakhulu kwiicytogenetics kwaye inokusetyenziswa kwedayi, idayi yeGiemsa, ukuvumela ukubonwa kwe-chromosomes. Obu buchule busebenza kakhulu ekufumaniseni utshintsho kumanani, ubukhulu becala, kunye nolwakhiwo kwi-chromosome, kuba yeyona nto iphambili ekusebenziseni i-cytogenetics yokufumanisa isifo kunye nokuqinisekisa i-Down syndrome, umzekelo, ebonakaliswa bubukho be-chromosome eyongezelelweyo;
• Indlela YOKULOBA yindlela ethe ngqo ngakumbi nebuthathaka, isetyenziselwa ngakumbi ukunceda ekuchongeni umhlaza, njengoko ivumela ukuba ichonge utshintsho oluncinci kwii-chromosomes kunye nokulungiswa kwakhona, ukongeza ekuchongeni utshintsho lwamanani kwii-chromosomes. Ngaphandle kokusebenza ngokukuko, ubuchule be-FISH bubiza kakhulu, kuba isebenzisa iprosesa ye-DNA enelebhile ye-fluorescence, efuna isixhobo sokubamba i-fluorescence kunye nokuvumela ukubonwa kwe-chromosomes. Ukongeza, kukho iindlela ezifumanekayo ngakumbi kwi-biology yeemolekyuli ezivumela ukufumanisa isifo somhlaza.

Ukulandela ukusetyenziswa kwedayi okanye iprosesa enelebheli, ii-chromosomes zilungelelaniswe ngokobungakanani, ngababini, isibini sokugqibela esihambelana nesini somntu, emva koko sithelekiswe nekariyamu eqhelekileyo, ngaloo ndlela kujongwa utshintsho olunokwenzeka.