Ezocansi zixhumene

Ukuxhuma okuxhunyaniswe ngocansi kuyindlela engavamile yokuthi isici noma ukuphazamiseka kungadluliswa emindenini. Isakhi sofuzo esisodwa esingajwayelekile ku-X chromosome singadala isifo esivelele esihlobene nocansi.

Imigomo ehlobene nezihloko zifaka:

• I-Autosomal ephezulu
• I-Autosomal ngokweqile
• I-Chromosome
• Gene
• Ufuzo nezifo
• Ifa
• Okweqile okuxhumene nobulili

Ifa lesifo esithile, isimo, noma isici sincike ohlotsheni lwe-chromosome ethintekile. Kungaba i-chromosome ye-autosomal noma i-chromosome yezocansi. Kuya futhi ngokuthi ngabe le mfanelo iyabusa noma ihlehlisile. Izifo ezixhumene nocansi zizuzwa nge-chromosomes eyodwa yocansi, eyi-X ne-Y chromosomes.

Ifa eliqavile livela lapho isakhi esingajwayelekile somzali oyedwa singadala isifo, noma ngabe isakhi sofuzo esifanayo esivela komunye umzali sijwayelekile. Uhlobo olungajwayelekile lubusa izakhi zofuzo.

Ngokuphazamiseka okukhulu okuxhunywe ku-X: Uma ubaba ephethe ufuzo olungajwayelekile lwe-X, wonke amadodakazi akhe azothola lesi sifo futhi akekho noyedwa emadodaneni akhe ozoba nalesi sifo. Lokho kungenxa yokuthi amadodakazi ahlala ezuza i-X chromosome kayise. Uma umama ephethe uhlobo olungajwayelekile lwe-X, uhhafu wazo zonke izingane (amadodakazi namadodana) uzodla ifa lokuthambekela kwesifo.

Isibonelo, uma kunezingane ezine (abafana ababili namantombazane amabili) futhi umama uthintekile (une-X eyodwa engavamile futhi unalesi sifo) kodwa ubaba akanalo ufuzo olungajwayelekile lwe-X, izingqinamba ezilindelekile yilezi:

• Izingane ezimbili (intombazane eyodwa nomfana oyedwa) bazoba nalesi sifo
• Izingane ezimbili (intombazane eyodwa nomfana oyedwa) ngeke zibe nalesi sifo

Uma kunezingane ezine (abafana ababili namantombazane amabili) nobaba ethintekile (une-X eyodwa engajwayelekile futhi unalesi sifo) kodwa umama akayona, amathuba alindelekile yilena:

• Amantombazane amabili azoba nalesi sifo
• Abafana ababili ngeke babe nalesi sifo

Lezi zingqinamba azisho ukuthi izingane ezizuza njengefa i-X engavamile zizokhombisa izimpawu ezinzima zalesi sifo. Ithuba lefa lisha ngomqondo ngamunye, ngakho-ke lezi zingqinamba ezilindelekile kungenzeka zingabi yilokho okwenzeka empeleni emndenini. Ezinye izifo ezixhunywe ku-X zinzima kakhulu kangangokuba abesilisa abanesifo sofuzo bangafa ngaphambi kokuzalwa. Ngakho-ke, kungahle kube nezinga elikhulayo lokukhulelwa kwesisu emndenini noma izingane zesilisa ezimbalwa kunokulindelekile.

Ifa - okuxhumene nocansi; Izakhi zofuzo - ziphezulu ezixhumene nobulili; Okuxhunywe ku-X okuphezulu; Okuxhunywe ku-Y

• Izakhi zofuzo

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