Ziziphi Iingxenye Zemzimba Zakho Zichaza Ngomlinganiselo Wakho Wokuguga
Ingaba iintso zakho, intliziyo okanye nokuba amabele akho aguge ngakumbi kunomzimba wakho wonke? Olunye uphando lubonisa ukuba akuzona zonke iindawo zomzimba wexesha elilinganayo . Ukufumanisa - ukuba kuyaqhubeka nokunika umlinganiselo wenjongo yokuba izicubu ezikhawulezayo ziguga - ekugqibeleni ziza kunceda izazinzulu zinciphise okanye ziguqule ukuguga.
Umgcini wexesha kwiiselitha
Inqaku elishicilelwe kwintlanganiso ka-Genome Biology ka-2013 ichaza indlela inkqubo yeekhemikhali yendalo eyenzeka ngayo ngaphakathi kweseli inokusetyenziswa njengoluhlobo lomgcini-mali okanye ukulinganisa ukuba isalathiso siyakhawuleza kangakanani.
Le nkqubo, eyaziwa ngokuba yi-methylation, iguqula i-DNA-iibhloko zokwakha izakhi zeeseli-kwipatheni ehambelana nokukhula.
Uphando oluphambili kwiYunivesithi yaseCalifornia eLos Angeles (UCLA) wasebenzisa ama-sampuli amathematika kuma-34 eembini zamawele afanayo ukubonisa ukuba yeyiphi iisayithi ze-DNA ezidibanisa i-methylation enokwethenjelwa kwiminyaka yezifundo. Iingcali zenzululwazi zazama ukuvavanya i-methylation rates kwinani labantu ababanzi kwaye banakho ukuphawula ngamnye umntu omdala kwiminyaka emihlanu, esebenzisa umlenze womntu kuphela.
USteve Horvath, u-UCLA womntu we-genetics kunye noprofesa we-biostatistics, wathatha olu phando kwaye waphonononga iimpawu ezingaphezu kwama-8 000 kunye neesampuli zeeseli ezinikezelwa ngabanye ososayensi. Iisampuli zomntu zathathwa ukususela ngaphambi kokuzalwa ukuya kwiminyaka eyi-101, ngaphaya kweengu-50 iintlobo ezahlukeneyo zezicubu kunye neeseli ezivela kwiindawo ezahlukeneyo zomzimba, kubandakanya isibindi, iinjongo, ingqondo, imiphunga kunye nentliziyo. I-DNA methylation rates yenza i-gauge engaguqukiyo yeendlela ezihamba ngokukhawuleza ngayo izicubu ezihlukahlukeneyo.
UHorvath kunye nabalingane bakhe basebenzise ukulinganisa ukulinganisa izinga lokuguga kuma-sampuli ehlukeneyo omhlaza wesi- 6 000, ezimele iintlobo ezingama-20 zesifo.
Iimpawu ezahlukeneyo zeBhunga leBakala kwiiRhafu ezahlukeneyo
Iqela leHorvath lafumanisa ukuba amaninzi ama-tissue yobudala ahamba kakuhle kakhulu; empeleni, iminyaka yabo yezinto eziphilayo , oko kukuthi baqhuba kakuhle kangakanani, balinganisa iminyaka yabo yokulandelana kweminyaka , oko kukuthi inani leminyaka elimelelwe kwikhalenda.
Nangona kunjalo, iisifuba zesifuba sasiyodwa. Iimfuyo ezincinci zeempilo zihamba ngokukhawuleza kwaye zisebenza kwiminyaka emibili ukuya kwimithathu emdala kunomzimba womfazi. Oku kunokucacisa ukuba kutheni umdlavuza webele usona hlobo luqhelekileyo lomhlaza kubasetyhini ukususela kwiminyaka yinto engumngcipheko kwaye izicubu ezinokukhawuleza ngokukhawuleza zingakwazi ukufumana umdlavuza.
Kubasetyhini abanesifo somdlavuza webele, ukuguga ngokukhawuleza kubaluleke nakakhulu. Izicubu zokuvavanya eziseduze neengxwaba zomhlaza zesifuba, abaphandi bafumanisa ukuba kwimizuzu engama- 12 ubudala kunomzimba wonke.
Ngaba iiseli eziguga ngokukhawuleza zithandwa ngakumbi kwiCarcer?
Izicubu ezinomdla zifunyenwe zibe zikhulu kunezicubu ezinempilo ezifunyenwe kwenye indawo emzimbeni. Iqela lophando liphonononga iintlobo ezingaphezulu kwe-20 ezahlukeneyo zomhlaza kwaye zifumene iimpawu ezihambelanayo zokuguga ngokukhawuleza kwiisampula ezigulayo. Enyanisweni, izicubu zomhlaza zaziphakathi kweminyaka engama-36 ubudala kunomzimba wonke.
Oku kubangela umbuzo obalulekileyo: Ngaba iiseli eziguga ngokukhawuleza zisengozini yomdlavuza okanye zenza amangqamuzana omhlaza womhlaza ngokukhawuleza? UHorvath uchaza ukuba zombini ezo zinto zinokuba yi nyaniso. Ngokomzekelo, kwiimeko ezininzi zomhlaza, izicubu eziseduze zibukeka ziyingcinci, okanye ubuncinci beminyaka yabantu beesampuli, ezibonisa umdlavuza ngokwawo amaseli.
Iqiniso lokuba ngisho nezicubu ezincinci zebele zibonakala zikhulile ngokwemilinganiselo ye-methylation xa kuthelekiswa nomnye umzimba womfazi ubonisa ukuba izicubu ezinokukhula ngokukhawuleza zingaba nomdlavuza.
"Kuya kufuneka ukuba kwenziwe uphando olongezelelweyo ukuvavanya le ngcamango," kusho uHorvath. Ngokuqinisekileyo sifuna ukulinganisa iminyaka yobudala besifo esinobuchopho, esingengomhlaza. Ngaphezu koko, sifuna ukuvavanya ukuba ukunyuka kweminyaka emathunzini esifuba kukuxhomekeke ekuphuculweni komhlaza kwithuba elizayo. "
Ukuvavanywa okuninzi kwezicathulo zesifuba esempilweni kwimibandela eyahlukeneyo yobomi bowesifazane - ukukhulelwa, emva kokutshatyalaliswa komva, emva kokukhulelwa nangemva kokuyeka umva - kuya kunceda ukucacisa ukuba iisisu zomzimba eziguga ngokukhawuleza, ngokwenene, ziyakwazi ukuvelisa umhlaza.
Ukuba kunjalo, ukuvavanya umlinganiselo weemethylation phakathi kwamabele kusenokwenzeka ngelinye ilanga litshatile ithuba lomfazi lokufumana izifo ezisongela ubomi.
Telomeres
I-Telomeres inikeza enye indlela yokulinganisa amazinga okuguga. I-Telomeres ziyizakhiwo ezincinci ezihambisa izinto zofuzo ngaphakathi kweseli njengoko iseli lilungele ukwahlula. Njalo ngexesha ukwahlukana kweeseli kwenzeka, i-telomeres iyanciphisa i-bit; xa bekuncinci kakhulu, iseli alinakukwazi ukwahlula, okubangele ukufa kweseli.
Kukho uphando oluqhubekayo ukulinganisa ubude be-telomere njengoluhlobo lwenjongo yokwenza ukuba iiseli ezinqamlekileyo emzimbeni wakho ziguga. Ukongezelela, izazinzulu ziphanda nokuba ukugcina i-telomeres ixesha elide kunokugcina iiseli ezincinci kwaye zihlule ngokufanelekileyo.
Imithombo:
Methylation. I-US National Cancer Institute Dictionary yeCancer Terms. Ifikelele ngo-Oktobha 25, 2013.
http://www.cancer.gov/dictionary?cdrid=655031
Steve Horvath. "I-DNA i-methylation yobudala bemithambo yabantu kunye neeseli zeentlobo." I-Genome Biology 2013, 14: R115.
http://genomebiology.com/2013/14/10/R115
Sven Bocklandt, Wen Lin, uMary E. Sehl, uFrancisco J. Sánchez, uJanet S. Sinsheimer, uSteve Horvath no-Eric Vilain. "I-Epigenetic Predictor Age." I-PLOS ONE 6 (6): e14821.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0014821