Nondisjunction ua rau Down syndrome li cas?
Nondisjunction ua rau Down syndrome li cas?

Video: Nondisjunction ua rau Down syndrome li cas?

Video: Nondisjunction ua rau Down syndrome li cas?
Video: Downs Poem 2024, Kaum ib hlis
Anonim

TUG 21 ( NONDISJUNCTION )

Down syndrome feem ntau yog ua rau los ntawm qhov yuam kev hauv cell division hu ua kev tsis sib haum xeeb .” Kev tsis sib haum xeeb ua rau lub embryo nrog peb daim ntawv theej ntawm chromosome 21 es tsis txhob siv ob qho tib si. Ua ntej los yog thaum xeeb tub, ib khub ntawm 21st chromosomes nyob rau hauv cov phev los yog lub qe tsis cais.

Kuj tseem paub yog, dab tsi yog qhov ua rau tus mob Down syndrome niam tsis muaj kev cuam tshuam?

Kwv yees li 96% ntawm cov neeg mob Down syndrome yog ua rau los ntawm kev tsis sib haum xeeb nyob rau hauv ob lub hlwb ntawm cov niam txiv, los yog lub qe fertilized (trisomy 21 los yog mosaicism). Nyob rau hauv ob qho tib si, qhov ua tsis tiav ntawm chromosome 21 los cais tsis yog ua rau los ntawm cov niam txiv muaj Down syndrome (txhais tau tias nws tsis yog qub txeeg qub teg).

Puas yog Down syndrome tshwm sim los ntawm kev tsis sib haum xeeb hauv meiosis 1 lossis 2? Kev tsis sib haum xeeb tshwm sim thaum homologous chromosomes ( meiosis Kuv) los yog tus muam chromatids ( meiosis II ) tsis cais thaum lub sij hawm meiosis . Feem ntau trisomy yog chromosome 21, uas ua rau Down syndrome.

Kuj tseem paub yog, meiosis ua rau Down syndrome li cas?

Down syndrome tshwm sim thaum lub nondisjunction tshwm sim nrog Chromosome 21. Meiosis yog ib hom kev faib cell tshwj xeeb siv los tsim peb cov phev thiab qe qe. Qhov feem ntau hom ntawm Down syndrome (Trisomy 21) tshwm sim thaum cov phev los yog qe nrog ib qho ntxiv Chromosome 21 koom ua ke nrog cov phev los yog qe nrog 23 chromosomes.

Down syndrome tshwm sim li cas?

Down syndrome yog ib hom kab mob caj ces ua rau thaum kev faib tawm ntawm tes txawv txav ua rau muaj ib qho ntxiv tag nrho lossis ib nrab daim ntawv theej ntawm chromosome 21. Cov khoom siv caj ces ntxiv no ua rau txoj kev loj hlob hloov thiab lub cev nta ntawm Down syndrome.

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