Kev tshuaj ntsuam genetic drift: yooj yim zog ntawm tus txheej txheem

DNA feem nyob rau hauv uas yog nyob ib yam noob locus yog hu ua. Nws tej zaum yuav muaj lwm versions ntawm kev tshuaj ntsuam genetic ntaub ntawv - alleles. Nyob rau hauv txhua pejxeem, muaj ib tug loj tus naj npawb ntawm cov ntaub ntawv lug. Yog li qhia tawm rau ntawm ib tug allele nyob rau hauv lub genome ntawm cov pejxeem yog lub npe ntawm cov noob frequencies.

Yuav kom ib tug tej yam hloov coj mus rau lub evolutionary hloov ntawm hom, nws zaus yuav tsum txaus siab, thiab cov mutant allele muaj yuav tsum tau tsau nyob rau hauv tag nrho cov tib neeg ntawm txhua tiam. Nrog ib tug me ntsis nyiaj ntawm nws mutational hloov tsis tau cuam tshuam rau lub evolutionary keeb kwm ntawm kab mob.

Yuav kom allele zaus loj hlob, yuav tsum ua tej yam yam - genetic drift, tsiv teb tsaws thiab tej yam ntuj tso xaiv.

kev tshuaj ntsuam genetic drift - qhov no yog ib tug random allele txoj kev loj hlob nyob rau hauv tus ntawm ob peb cov txheej xwm uas muab thiab muaj ib tug stochastic cim. Qhov no txoj kev yog txuas mus rau qhov tseeb hais tias tsis yog txhua txhua tus neeg nyob rau hauv cov pej xeem muab kev koom tes nyob rau hauv tu tub tu kiv. Nws yog feem ntau cov yam ntxwv ntawm cov tsos mob los yog cov kab mob uas tsis tshua muaj, tab sis vim yog cov tsis muaj kev xaiv yuav tsum muab cia rau hauv lub tsev neeg los yog txawm rau tag nrho cov neeg nyob ntawm ib tug me me luaj li cas rau ib ntev lub sij hawm. Qhov nov yeej yog feem ntau pom nyob rau hauv ib tug me me pejxeem, tus xov tooj uas yog tsis ntau tshaj li 1,000 cov neeg, vim hais tias nyob rau hauv cov ntaub ntawv no yog tsis tshua muaj me me tsiv teb tsaws.

Nyob rau hauv thiaj li yuav to taub zoo dua cov kev tshuaj ntsuam genetic drift, yuav tsum tau paub txog tej kev cai lij choj. Nyob rau hauv tus neeg mob qhov twg lub allele zaus yog 0, nyob rau hauv succeeding tiam nws tsis hloov. Yog hais tias nws nce mus txog 1, ces peb hais tias cov noob nyob rau hauv cov pejxeem yog tsau. Random caj drift thiab yog ib lub txim ntawm lub kho cov txheej txheem nrog simultaneous tsis ntawm ib tug allele. Feem ntau cov feem ntau, qhov no qauv yuav tsum havzoov thaum lub hloov thiab tsiv teb tsaws tsis ua tas mus li hloov nyob rau hauv lub Cheebtsam ntawm loci.

Txij li thaum cov noob zaus muaj ib tug uas tsis yog-directional cim, nws thiaj li muaj ntau haiv neeg ntawm hom, thiab kuj yuav tsub qhov txawv ntawm lub zos coob. Nws yog ib nqi sau cia hais tias qhov no counteracts tus tsiv teb tsaws, nyob rau hauv uas nyias pawg ntawm cov kab mob no qhia lawv alleles. Peb kuj yuav tsum hais tias kev tshuaj ntsuam genetic drift twb yuav luag tsis ntxim rau cov zaus ntawm ib tug neeg cov noob nyob rau hauv loj coob, tab sis nyob rau hauv tej pawg me me, nws yuav ua tau ib tug decisive evolutionary tau. Cov nab npawb ntawm cov alleles yog hloov dramatically. Ib txhia noob tej zaum yuav irretrievably poob, uas zoo heev impoverishes lub caj haiv.

Raws li ib qho piv txwv, loj mob kev nkeeg, tom qab uas cov pejxeem tau nqa tawm suab rov qab vim nws ob peb cov neeg sawv cev. Ntxiv mus, tag nrho cov me tub me nyuam twb zoo tib yam txwv zeej txwv koob noob. Tom qab expansion allelic muaj ntau haiv neeg ensured Asmeslikas manufacturers los yog cov departing nabkaus uas txhawb txoj kev loj hlob txawv ntawm cov kev tshuaj ntsuam genetic theem.

Huab manifestation ntawm kev tshuaj ntsuam genetic drift yuav hu tsos lig tshiab pejxeem uas yog tsim los ntawm tsuas ib ob peb cov neeg - qhov thiaj li hu ua tus tsim cov nyhuv.

Nws yuav tsum tau hais tias cov qauv ntawm genome restructuring kawm biotechnology. Genetic engineering - ib tug txheej txheem ntawm no science, uas tso cai rau koj mus rau cov hloov kev tshuaj ntsuam genetic ntaub ntawv. Thaum zoo li no noob hloov tso cai rau kom nrog lub hom teeb meem thiab impart yam zog kab mob.