Kwezakhi zabantu. ukuguqulwa kwezakhi zofuzo Chromosomal e abantu

abantu Kwezakhi limelela izinguquko ezenzeka yeseli ezingeni DNA. Zingaba zezinhlobo ezahlukene. Kwezakhi zabantu kungaba hlangothi. Kulokhu, lapho kuyinto yinye esikhundleni nucleoid. Izinguquko zingaba yingozi. Basuke izimpawu umphumela okukhulu phenotypic. Futhi abantu kuguquka angase abe wusizo. Kulokhu, izinguquko nethonya ezincane phenotypic. Manje, ake sihlole kabanzi indlela kuguquka womuntu. Izibonelo izinguquko uzonikezwa esihlokweni.

ngezigaba

Thola izinhlobo ezahlukene ukuguquka kwezakhi zofuzo. Ezinye izigaba kukhona yena, ngezigaba lalo. Ikakhulukazi, kukhona ukuguquka kwezakhi zofuzo ezilandelayo:

• Ukuphathwa kwabathintwayo.
• Chromosome.
• Cytoplasmic.
• ukuguqulwa kwezakhi zofuzo ocwaningweni kubantu kanye nezinye izilwane.

Izinguquko ezenzeka ngaphansi kwethonya izici ezihlukahlukene. Elinye lamacala esicace ushintsho olunjalo kubhekwe eChernobyl. Ukuguqula izakhi zofuzo zabantu ngemva kwale nhlekelele kwaqala ukuvela ngokushesha. Nokho, ngokuhamba kwesikhathi baba ngaphezulu futhi evelele.

Human chromosomal kuguquka

Lezi zinguquko zinezikhathi kwezinso kwesakhiwo. I amakhefu chromosome zenzeka. Basuke ephelezelwa rearrangements ezahlukene isakhiwo. Kungani kukhona ukuguqula izakhi zofuzo lomuntu? Isizathu siwukuthi kule izici zangaphandle:

• Physical. Lezi zihlanganisa i-gamma futhi-X ray, ultraviolet ukuchayeka, izinga lokushisa (kuphakeme / kuphasi), i-kagesi ensimini, ingcindezi, kanye nokunye.
• Chemical. Lokhu kuhlanganisa alcohols, cytostatics, esindayo zensimbi, phenols nezinye izingxube zamakhemikhali.
• Eziphilayo. Lezi zihlanganisa lamagciwane.

ukuhlelwa kabusha nokuguqulwa

Kwezakhi zabantu kuleli cala kuphakama ngaphansi kwezimo ezivamile. Kodwa-ke izinguquko ezinjalo zitholakala nature ezingavamile kakhulu: 1 amakhophi angaphezu kwesigidi e isakhi esithile 1-100 amacala. Usosayensi JBS Haldane ibalwa amathuba isilinganiso ukulungiswa okuzenzakalelayo. Kwakuyisikhathi isizukulwane 5 * 10-5. Okuzenzekelayo inqubo ukuthuthukiswa kuxhomeke ezicini wangaphandle futhi yangaphakathi - mutational ingcindezi ophansi.

sici

ukuguqulwa kwezakhi zofuzo Chromosomal anesizotha labizwa ngokuthi elimazayo. Pathologies ukuthi ukuthuthukisa ngenxa reorganizations, ngokuvamile aluhambisani nawo ekuphileni. Njengoba izici eziyisisekelo chromosomal ukuguquka kwezakhi zofuzo umusa ukulungiswa ngephutha. Ngenxa kubo kwakhiwa amaningi "sokusebenzisana" entsha. Lezi zinguquko reshaping umsebenzi isakhi sofuzo, ukusabalalisa izakhi kulo ufuzo ngengozi. Inani labo oluhambelana kunqunywa inqubo Ukukhetha.

ukuguqulwa kwezakhi zofuzo Chromosomal: ngezigaba

Kukhona ezintathu ongakhetha izinguquko ezinjalo ziyathandeka. Ikakhulukazi, iso elingalodwa, abaFu- ndi futhi ukuguquka kwezakhi zofuzo intrachromosomal. Kugcine libhekene kwezinso (aberatsiyami). Basuke zikhonjwe kohlaka chromosome eyodwa kuphela. Lokhu izinguquko zeqembu zihlanganisa:

• Okususiwe. Lezi ukuguquka kwezakhi zofuzo amelela ukulahlekelwa sangaphakathi noma ekupheleni ingxenye chromosome. Kabusha lolu hlobo kungabangela eziningi anomalies phakathi ukuthuthukiswa embryonic (isibonelo, inhliziyo azalwa naso isici uhlobo).
• Kombhala. Lolu shintsho kuhilela ukujikeleza isinqamu chromosome degrees 180. nokusetha kusayithi wangaphambili. Kulokhu, i-oda timphawu tesakhiwo siphukile, kodwa lokhu akuphazamisi phenotype, uma azikho izinto ezengeziwe.
• Duplications. Zimelela ukubuyabuyelela chromosome isinqamu. ukuphambuka okunjalo kusukela kuyinsakavukela kuphakamisa ukuguquka kwezakhi zofuzo lomuntu heritable.

ukulungiswa Interchromosomal (translocations) umklomelo phakathi izakhi izingxenye lapho izakhi zofuzo ezifanayo. Lezi zinguquko zihlukaniswe zibe:

• Robertsonian. Yakheke esikhundleni umsindo chromosome amabii metacentric acrocentric.
• Nonreciprocal. Kulokhu, ingxenye ezihambayo eyodwa chromosome kwenye.
• Okuhambisanayo. Ngaphansi kwalezi rearrangements umklomelo phakathi izici ezimbili ngokuyinhloko.

kuphakama Izohromosomnye ukuguquka kwezakhi zofuzo ngenxa ukwakheka chromosomal amakhophi esibukweni sites nezinye ezimbili, aqukethe okufanayo isakhi sofuzo amasethi. ukuphambuka okunjalo kusukela kuyinsakavukela okubhekiselwe kwakwakhe centric ngenxa yokuthi engu- chromatid ngokuhlukana okwenzeka ngo centromere.

Nazi izinhlobo izinguquko

Kukhona kwesakhiwo zezinombolo chromosomal ukuguquka kwezakhi zofuzo. Lesi sakamuva, esikhundleni salokho, zihlukaniswe aneuploidy (lokhu ukubukeka (trisomy) noma ukulahleka (monosomy) izakhi ezengeziwe) kanye polyploidy (ukuthi ukwanda okuphindwe kayishumi izinombolo zabo). kabusha kwesakhiwo ethulwa inversions, okususiwe, translocations, okufakiwe, futhi isochromosome izindandatho centric.

Ukuxhumana yemihlobo ehlukeneko rearrangements

ukuguqulwa kwezakhi zofuzo ocwaningweni izinguquko ezahlukene inani timphawu tesakhiwo. Zofuzo kukhona ukushayisana isakhiwo ezakhini zofuzo. ukuguqulwa kwezakhi zofuzo Chromosomal kuthinte isakhiwo chromosome ngokwabo. Nesibongo, esikhundleni salokho, kufanele ngezigaba ofanayo polyploidy futhi aneuploidy. Kabusha ushintsho phakathi kwawo kuyinto translocation Robertsonian. Lezi ukuguquka kwezakhi zofuzo ehlangana isiqondiso esinjalo, kanye Umqondo wokwelashwa njengoba "angahlangani chromosomal". Kuhlanganisa:

• zokugula ukuphathwa kwabathintwayo. Lezi zihlanganisa zokugula ngemisebe, isibonelo.
• iziyaluyalu Intrauterine. Kungaba izisu nokuguqulwa, libangela ukuphuphuma kwezisu.
• izifo Chromosomal. Lezi zihlanganisa i-Down Syndrome, nabanye.

Okwamanje, cishe sasiyikhulu namashumi anomalies eyaziwa. Bonke bafunda futhi baba kuchazwe. Njengoba syndromes kuboniswe amafomu mayelana 300.

Izici kwezinso azalwa naso

ukuguqulwa kwezakhi zofuzo Ukubambezeleka ethulwa sasivumela kakhulu. Lesi sigaba libhekene ukukhubazeka amaningi ekuthuthukisweni. Kwakheka ngenxa ukwephula izinguquko eziphawuleka kakhulu kuyi-DNA. Izilonda zenzeka ngesikhathi sokukhulelwa, nokuvuthwa gamete, izigaba sokuqala ukwehlukana iqanda. Ukwehluleka singenzeka ngisho nalapho ukuhlanganisa amaseli ephelele yabazali. Le nqubo namuhla namanje ayikwazi ukulawulwa kanye kungukuthi ngokugcwele.

Imiphumela izinguquko

Izinkinga of chromosomal ukuguquka kwezakhi zofuzo avame ukuba ezingezinhle kakhulu kumuntu. Ngokuvamile bephambana:

• Ngo-70% - isisu nokuguqulwa.
• Kombungu.
• Ngezinye 7.2% - ukuzalwa kwengane isishonile.
• Ukwakheka izimila.

Against isizinda ezingeni chromosomal kwezinso izilonda kwezitho zomzimba kubangelwa izici ezihlukahlukene: uhlobo anomalies, impahla ngokweqile noma lokungakeneli chromosome ngabanye, zezemvelo, le genotype umzimba.

amaqembu pathologies

Zonke isifo chromosomal zihlukaniswe ngezigaba ezimbili. Eyokuqala ukuphulwa sokucasuka ku izakhi eziningi. Lezi pathologies bakha ingxenye enkulu yomsebenzi izifo chromosomal. Ngaphandle trisomies, monosomy nezinye izinhlobo polysomes kuleli qembu zihlanganisa tetraploidy futhi triploidy (lapho befa kwenzeka noma esibelethweni noma amahora ambalwa zokuqala ngemva kokuzalwa). Ngokuvamile Kutholwe i-Down Syndrome. Kusekelwe ukukhubazeka kwezakhi zofuzo. Down syndrome yaqanjwa igama wezingane, ngubani owachaza lesi sifo ngo-1886. Njengamanje, lo syndrome kakhulu wafunda kuzo zonke kwezinso chromosomal. Angahlangani kwenzeka cishe ngo okukodwa kokungamashumi 700. Isigaba sesibili sihlanganisa izifo ezibangwa tingucuko tekuhleleka chromosome. Izimpawu lezi pathologies zihlanganisa:

• Ukukhula retardation.
• retardation kwengqondo.
• ekhaleni Roundness.
• Deep iso kokwehla.
• Inhliziyo yayo yayinezinkinga ezicini (azalwa naso) nabanye.

Ezinye izifo ezibangwa ushintsho inani lezakhi zofuzo ocansini. Iziguli ukuguquka kwezakhi zofuzo abanjalo nanzalo. Kuze kube manje, akukho Ayalandelana ukwelashwa etiological izifo ezinjalo. Nokho, isifo kungagwenywa izindlela ukuxilongwa kokubeletha.

Indima ukuvela

Against ngemuva izinguquko okukhulu izimo yezinguquko ngaphambili owayengenalusizo elimazayo kungaba wusizo. Ngenxa ukulungiswa okunjalo abhekwa impahla yokukhethwa. Uma kuguquka alithintwa yi "buthule" izingcezwana DNA noma yena kuphakamisa esikhundleni esisodwa isinqamu ikhodi kuyahambisana, njengoba umthetho, awusebenzi ukuzibonakalisa nganoma iyiphi indlela kule phenotype. Nokho, ukulungiswa okunjalo kungatholakala. Ngenxa yale njongo, izindlela isakhi sofuzo ukuhlaziywa. Ngenxa yokuthi izinguquko zenzeka ngenxa ukuchayeka nezinto zemvelo, khona-ke, sizitshele ukuthi umuntu izici eyinhloko imvelo uhlala ingashintshiwe, kubonakala ukuthi ukuguquka kwezakhi zofuzo avele cishe at a imvamisa njalo. Leli qiniso singasetshenziswa ekuhloleni phylogeny - ukuhlaziywa nokuzwelana nomsuka taxa ezahlukene, kuhlanganise nomuntu. Mayelana nale ndlela entsha "izakhi zofuzo buthule" advocate kubacwaningi njengendlela "iwashi yamangqamuzana ezinto eziphilayo." Imfundiso lusekelwe futhi yokuthi iningi izinguquko angathathi hlangothi. isilinganiso sabo sokuzuza isakhi esithile ibuthakathaka noma ukuzimela ngokuphelele bangabi ngaphansi kwethonya ukuzihlela nokuzivumelanisa kwemvelo. Ngenxa yalokho we kuguquka kuba njalo isikhathi eside. Nokho, i-izakhi zofuzo ezihlukahlukene umfutho bazoba ngabanikazi.

Ekuphetheni

Ucwaningo indlela nesenzakalo, ukuqhubeka rearrangements ku mitochondrial-deoxyribonucleic acid, okuyinto iguqulwe enzalweni ngokusebenzisa umugqa kwabakhulelwe, futhi i-Y-chromosomes e, basukile uyise, sisetshenziswa kabanzi namuhla ngokwanele eziphilayo ezikholelwa ekuziphendukeleni kwemvelo. Kwaqoqwa, sikuhlaziye izinto systematized, imiphumela yocwaningo zisetshenziselwa ukwenza izifundo umsuka bezizwe ezihlukahlukene nezinhlanga. Okubaluleke kakhulu kukhona ulwazi maqondana kabusha ukwakheka kwezinto eziphilayo kanye nokuthuthukiswa kwesintu.