PCR, ama falcelinta silsiladda polymerase, waa farsamo loo isticmaalo in lagu kordhiyo taxanaha DNA.Waxaa markii ugu horreysay soo saartay 1980-meeyadii Kary Mullis, kaasoo ku abaalmariyay abaalmarinta Nobel Prize ee Kimistariga 1993-kii shaqadiisa.PCR waxa ay wax ka bedeshay bayoloji molecular, taas oo awood u siisay cilmi baadhayaashu in ay DNA ka soo kordhiyaan muunado yaryar oo ay si faahfaahsan u daraaseeyaan.
PCR waa hannaan saddex-tallaabo ah oo ka dhaca wareegga kulaylka, mashiin si degdeg ah u beddeli kara heerkulka isku-darka falcelinta.Saddexda tillaabo waa denaturation, annealing, iyo fidinta.
Talaabada kowaad, denaturation, DNA-ga laba-geesoodka ah waxaa lagu kululeeyaa heerkul sare (badanaa qiyaastii 95 ° C) si loo jebiyo curaarta hydrogen ee isku haya labada xadhig.Tani waxay keenaysaa laba unug oo DNA ah oo hal xarig ah.
Talaabada labaad, soo-jiidashada, heerkulka ayaa hoos loo dhigayaa ilaa 55 ° C si loogu oggolaado furayaasha inay dhuujiyaan taxanaha is-kaabaya ee DNA-da hal-xidhaale leh.Furayaasha waa qaybo gaagaaban oo DNA ah kuwaas oo loo qaabeeyey inay la jaanqaadaan taxanaha xiisaha DNA-da la beegsanayo.
Tallaabada saddexaad, kordhinta, heerkulka ayaa kor loogu qaadayaa ilaa 72 ° C si loogu oggolaado Taq polymerase (nooc ka mid ah DNA polymerase) inuu ka sameeyo qayb cusub oo DNA ah oo ka soo jeeda aasaasayaasha.Taq polymerase waxaa laga soo qaatay bakteeriyada ku nool ilo kulul oo awood u leh inay u adkeysato heerkulka sare ee loo isticmaalo PCR.
Kadib hal wareeg oo PCR ah, natiijadu waa laba nuqul oo isku xigxiga DNA-da la beegsaday.Ku celcelinta saddexda tallaabo ee tiro wareegyo ah (sida caadiga ah 30-40), tirada koobiyada taxanaha DNA-da ee bartilmaameedka ah ayaa loo kordhin karaa si xad dhaaf ah.Tani waxay ka dhigan tahay in xitaa qadar yar oo DNA-da bilawga ah la kordhin karo si loo soo saaro malaayiin ama xitaa balaayiin nuqul.
PCR waxay leedahay codsiyo badan oo xagga cilmi-baarista iyo ogaanshaha.Waxaa loo adeegsadaa hidda-socodka si loo barto shaqada hiddo-wadaha iyo isu-beddelka, cilmi-baadhisyada si loo falanqeeyo caddaynta DNA-da, ogaanshaha cudurrada faafa si loo ogaado joogitaanka cudur-sidaha, iyo baaritaanka dhalmada ka hor si loo baadho cilladaha hidde-socodka ee uurjiifka.
PCR waxa kale oo loo habeeyey in loo isticmaalo tiro kala duwanaansho ah, sida PCR tirada (qPCR), kaas oo u ogolaanaya cadadka DNA-da in la cabbiro oo dib loo dhigo qoraalka PCR (RT-PCR), kaas oo loo isticmaali karo in lagu kordhiyo taxanaha RNA.
Inkasta oo ay jiraan codsiyo badan, PCR waxay leedahay xaddidaadyo.Waxay u baahan tahay aqoonta isku xigxiga bartilmaameedka iyo naqshadaynta asaasiga ah ee ku habboon, waxayna u nugul tahay khalad haddii xaaladaha falcelinta aan si sax ah loo hagaajin.Si kastaba ha ahaatee, iyadoo si taxadar leh loo naqshadeeyay iyo fulinta tijaabada ah, PCR ayaa weli ah mid ka mid ah qalabka ugu awoodda badan bayoloji molecular.
Waqtiga boostada: Febraayo-22-2023