I-karyotype yama-chromosomes akho ingathola noma yiziphi izinkinga
Kuzo zonke izinhlobo zomzimba, kusukela kubantu kuya ezitshalweni, ziyizikhungo ezincane zokwakha ezibizwa ngokuthi amangqamuzana. Lawa maseli ahluke ngezinhlobo zazo futhi ngaphakathi komuntu ngamunye, isilwane, noma uzitshale ngokwawo. Kulawo maseli kukhona ama-chromosomes aqukethe i-DNA, isakhiwo sendlela esisebenza ngayo. Ngezinye izikhathi, noma ukuthola umqondo ongcono wokuthi sisebenza kanjani noma sihlolisisa izimo zezokwelapha, isithombe, esibizwa ngokuthi i- karyotype , sithathwa ngamacromosomes ethu.
I-karyotype iyindlela ejwayelekile kakhulu yokuhlaziya ama- chromosomes womuntu. Kungenziwa kunoma yiziphi izicubu zomuntu kodwa ngokuvamile kuyenziwa ngegazi, isikhumba, amniotic fluid, noma i-chorionic villi. Amaseli athathwe ebhodini, ekhulile noma ekhuliswe, agqoke amaslayidi, izithombe, futhi ahlaziywe.
I-Karyotype Ingakutshela Kanjani?
I-karyotype ingakutshela ukuthi zingaki ama-chromosomes umuntu anakho kanye nesakhiwo se-chromosome ngayinye. Ngenxa yokuthi i-karyotype ikunika ulwazi mayelana ne-chromosome ngayinye, ingakutshela ubulili bomuntu ngamunye. Uma ama-chromosome amabili e-X ekhona, lowo muntu uyisifazana. Uma i-X ne-Y chromosome ikhona, khona-ke lowo muntu uyindoda.
Ngenxa yokuthi i-karyotype inikeza ulwazi mayelana nenani lama-chromosomes okwamanje, lingathola izimo ezifana ne-Down syndrome - ukuba khona kwe-chromosome yenombolo engu-21 (ama-chromosomes angu 47 angu-total, kunama-46). I-karyotype iphinda ibheke isakhiwo se-chromosome ngayinye, ngakho-ke ingathi uma umuntu ethwala izinkinga ze-chromosome zesakhiwo njenge- translocation noma ukususwa.
(Amaphesenti angaba ngu-2 kuya kwezingama-3 we-Down syndrome amacala ngenxa yokuthutha okubandakanya i-chromosome yenombolo engu-21.)
I-Karyotype Ihluke Kanjani Nokuhlaziywa Kwe-FISH?
I-karyotype ihluke ekuhlaziyweni kwe- fluorescent in hybridization (FISH) ngoba ibukeka kahle kakhulu kuwo wonke ama-chromosomes umuntu anayo.
Ukuhlaziywa kwe-FISH kukunika ulwazi oluncane mayelana nawo wonke ama-chromosomes. Ukuhlolwa kwe-FISH kungabonakalisa ama-trismi - njenge-Down syndrome. Noma kunjalo, ngeke ukwazi ukukunikeza ulwazi njengezithombe njengekaryotype. I-karyotype izophinde ibone umehluko wesakhiwo ezifana nokudluliselwa, ukususa, ukuchithwa kwama-chromosomes, nabanye.
Imiphumela ye-Karyotype ithatha isikhathi eside ukuze ibuyele emuva kuneleyo yokuhlaziywa kwe-FISH. I-karyotype eyenziwa ngamaseli egazi ingathatha noma yikuphi kusukela ezinsukwini ezintathu kuya kweziyisikhombisa. I-karyotype yama-amniocytes (amaseli avela ku-amniocentesis) noma isampula ye-chorionic villus ingathatha noma yikuphi kusukela ezinsukwini ezingu-10 ukuya kwezingu-14, kuye ngokuthi amasethini akhula ngokushesha kangakanani. Ukuhlaziywa kwe-FISH kuzobuya phakathi kwezinsuku ezintathu kuya kwezine.
Ukukhetha Uhlobo Lokuhlola Olufanele
Uma ucabangela ukuhlolwa kokubeletha noma i-karyotype ngezizathu zokuxilonga, kufanele uxoxe ngokuthi iyiphi inketho efanelekile ngendaba yakho ethize. Ungase futhi ufune ukuxoxa futhi uphenye ukuthi ngabe umshuwalense uzosibekela yini izindleko zokuhlaziywa kwe-FISH kanye ne-karyotype. Uma ukhulelwe ukukhulelwa kakhudlwana, udokotela wakho angancoma ukuhlolwa kwe-FISH kanye ne-karyotype, ukuze imiphumela yokutholwa itholwe ngokushesha. Imiphumela esheshayo ingafisa kulabo abaqhubekayo ekukhulelweni kwabo.
SOURCES:
I-American College of Obstetricians and Gynecologists (ACOG). Ukuhlola ukukhubazeka kwe-Fetal Chromosomal. I-ACOG Practice Bulletin, inombolo 77, January 2007.
I-National Human Genome Research Institute. I-Fluorescence In Hybridization (FISH), ngo-2008.