Qhov sib txawv tseem ceeb ntawm kev tsis sib haum xeeb thiab kev hloov pauv hloov pauv yog qhov kev hloov pauv uas tsis yog kev hloov pauv yog qhov hloov pauv uas tshwm sim vim qhov tsis ua tiav ntawm kev sib cais ntawm homologous chromosomes lossis chromatids thaum lub sijhawm sib faib ntawm tes thaum hloov pauv hloov pauv yog kev hloov pauv uas tshwm sim vim yog Kev hloov pauv ntawm qhov sib txawv ntawm chromosomes ntawm cov chromosomes uas tsis yog homologous.
Kev hloov pauv yog kev hloov pauv ntawm nucleotide ib ntus ntawm DNA molecule hauv genome ntawm ib yam kabmob. Yog li, kev hloov pauv tshwm sim feem ntau yog vim qhov ua tsis tiav ntawm kev faib cell (mitosis thiab meiosis). Yog li ntawd, nyob ntawm seb hom kev hloov pauv, nws cov nyhuv txawv. Raws li, nondisjunction mutation thiab translocation mutation yog ob hom kev hloov pauv loj uas tshwm sim thaum lub sijhawm cell faib.
Dab tsi yog kev hloov pauv tsis sib haum?
Nondisjunction hais txog qhov tsis ua tiav hauv kev sib cais ntawm homologous chromosomes lossis chromatids thaum lub sijhawm mitosis lossis meiosis. Txawm li cas los xij, cov txiaj ntsig ntawm kev tsis sib haum xeeb sib txawv ntawm cov mitosis thiab meiosis. Hauv mitosis, nondisjunction ua rau ntau yam qog nqaij hlav. Nyob rau hauv meiosis, nondisjunction ua rau ob lub hlwb sib txawv; ib tug ntxhais cell muaj ob niam txiv chromosomes nrog rau lwm tus ntxhais cell tsis muaj. Yog li ntawd, qhov no ua rau muaj kev hloov pauv ntawm cov chromosomes vim muaj cov chromosome ntxiv lossis tsis muaj chromosome.
Cov kab mob chromosomal uas tshwm sim vim tsis muaj kev cuam tshuam thaum lub sij hawm meiosis yog Down's syndrome, Klinefelter's syndrome, Turners's syndrome, thiab lwm yam. Down's syndrome lossis Trisomy 21 tshwm sim vim tsis muaj kev cuam tshuam ntawm chromosome 21 thaum lub sij hawm meiosis uas tus neeg tau txais peb daim ntawv theej ntawm chromosome. 21 es ob. Yog li, tus neeg uas muaj tus mob Down's syndrome muaj 47 chromosomes es tsis yog 46.
Daim duab 01: Kev hloov pauv tsis sib xws
Turners' syndrome tshwm sim vim tsis muaj kev sib deev ntawm chromosomes thaum lub sij hawm meiosis. Tus neeg mob muaj 45 chromosomes nrog ib leeg X chromosome. Lub sij hawm uas hais txog qhov kev hloov pauv no yog monosomy ntawm X poj niam txiv neej chromosome. Nyob rau hauv xws li ib tug neeg, kev sib deev genotype yog XO. Txawm li cas los xij, kev tsis sib haum xeeb hauv ob qho tib si mitosis thiab meiosis ua rau muaj kab mob tuag taus.
Dab tsi yog Translocation Mutations?
Nyob rau hauv cov ntsiab lus ntawm noob caj noob ces, translocation yog ib tug chromosomal abnormality uas tshwm sim vim rearrangement ntawm txawv qhov chaw ntawm chromosomes ntawm non-homologous chromosomes. Yog li, qhov txawv txav no feem ntau ua rau muaj kev hloov pauv tsis zoo xws li mob qog noj ntshav thiab muaj menyuam tsis taus. Nws yog ib qho yooj yim los txheeb xyuas chromosomal translocations los ntawm cytogenetics lossis los ntawm karyotyping ntawm cov hlwb cuam tshuam. Ntxiv mus, translocations tshwm sim inter-chromosomally los yog intra-chromosomally. Interchromosomal translocations tshwm sim nyob rau hauv ib tug chromosomes thaum intrachromosomal translocations tshwm sim ntawm chromosomes. Thaum lub sijhawm hloov pauv hloov pauv, ib feem ntawm cov chromosome tawg tawm thiab rov koom nrog lwm qhov chaw.
Tsis tas li, muaj ntau pawg ntawm kev hloov pauv hloov pauv; lawv yog cov sib npaug, tsis sib npaug, sib cuam tshuam, thiab tsis sib xws. Ua ntej, nyob rau hauv sib npaug translocations, sib npaug sib pauv ntawm cov ntaub ntawv yuav siv qhov chaw tsis muaj ntxiv los yog ploj lawm cov ntaub ntawv genetic. Txawm li cas los xij, kev hloov pauv tsis sib xws ua rau muaj qhov ntxiv lossis cov noob ploj vim muaj qhov sib txawv ntawm cov khoom siv chromosome. Nyob rau hauv reciprocal translocations, kev sib pauv ntawm cov khoom siv caj ces tshwm sim ntawm cov chromosomes uas tsis yog homologous. Thaum kawg, hauv kev hloov pauv tsis sib xws ntawm cov khoom siv caj ces tshwm sim los ntawm ib qho chromosome mus rau cov chromosome uas tsis yog homologous.
Daim duab 02: Kev hloov pauv hloov pauv
Kev hloov pauv chaw ua rau mob qog noj ntshav xws li leukemia, infertility thiab XX txiv neej syndrome, thiab lwm yam. Infertility tshwm sim thaum ib tug ntawm cov niam txiv nqa ib tug balanced translocation uas ua rau lub fetus tsis tau txawm tias niam txiv xeeb tub. XX txiv neej syndrome tshwm sim vim kev hloov pauv ntawm SRY noob ntawm Y chromosome rau X chromosome.
Dab tsi yog qhov zoo sib xws ntawm Nondisjunction thiab Translocation Mutations?
- Nondisjunction and Translocation Mutations yog genetic mutations.
- Lawv ob leeg tuaj yeem tshwm sim thaum lub sijhawm mitosis thiab meiosis.
- Tsis tas li ntawd, ob hom ua rau mob qog noj ntshav thiab Down's syndrome.
- Tsis tas li, ob leeg tuaj yeem cuam tshuam kev sib deev chromosomes.
Dab tsi yog qhov txawv ntawm Nondisjunction thiab Translocation Mutations?
Nondisjunction thiab translocation mutations yog kev hloov pauv ntawm nucleotide sequences ntawm DNA molecules uas tuaj yeem ua rau ntau yam kab mob. Nondisjunction mutations tshwm sim vim tsis ua hauj lwm ntawm homologous chromosomes los yog chromatids cais kom raug thaum lub sij hawm cell division. Ntawm qhov tod tes, kev hloov pauv hloov pauv tshwm sim vim kev hloov pauv ntawm qhov sib txawv ntawm chromosomes ntawm chromosomes tom qab tawg tawm ntawm ib chromosome. Yog li, nondisjunction mutations ua rau txawv txav ntawm tus naj npawb ntawm chromosomes nyob rau hauv ib lub xovtooj ntawm tes thaum translocation mutations ua structural abnormalities ntawm chromosomes nyob rau hauv lub genome ntawm kab mob. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm kev tsis sib haum xeeb thiab kev hloov pauv hloov pauv.
Cov hauv qab no infographic ntawm qhov sib txawv ntawm kev tsis sib haum xeeb thiab kev hloov pauv qhov kev piav qhia ntau dua.
Summary – Nondisjunction vs Translocation Mutations
Kev hloov pauv tshwm sim vim qhov ua yuam kev ntawm kev faib cell. Nondisjunction mutation yog qhov tsis ua tiav hauv kev sib cais ntawm homologous chromosomes lossis chromatids thaum lub sijhawm mitosis lossis meiosis. Hauv ntej, qhov no yog qhov sib txawv ntawm kev tsis sib haum xeeb thiab kev hloov pauv hloov pauv.
Tsis tas li ntawd, cov txiaj ntsig ntawm kev tsis sib haum xeeb sib txawv hauv mitosis thiab meiosis. Hauv mitosis, kev tsis sib haum xeeb ua rau mob qog noj ntshav. Cov kab mob chromosomal uas tshwm sim vim tsis muaj kev cuam tshuam thaum lub sij hawm meiosis yog Down's syndrome, Klinefelter's syndrome thiab Turners syndrome. Ntawm qhov tod tes, kev hloov pauv hloov pauv yog qhov txawv txav ntawm chromosomal uas tshwm sim vim qhov kev hloov pauv ntawm qhov sib txawv ntawm cov chromosomes uas tsis yog homologous. Inter-chromosomal, intra-chromosomal, balanced, unbalanced, reciprocal, thiab non-reciprocal translocations yog hom kev hloov pauv hloov pauv.
