Waa maxay qaybaha jidhkaaga ee kaaga muuqda qiyaastaada da'daada
Kelyahaaga, wadnahaaga ama xitaa naasahaaga miyuu ka soo reyn karaa dhaqdhaqaaqa jirka intiisa kale? Cilmi-baarisyada qaarkood waxay soo jeedinayaan in dhammaan qaybaha jidhka ee da'doodu tahay isla heerka . Helitaanka - haddii ay sii wado in ay bixiso qiyaas ujeedo ah sida unugyada degdegga ah ee gaboobay - waxay ugu dambeyntii u caawin kartaa aqoonyahannada in ay hoos u dhigaan ama xitaa ka noqdaan habka gabowga.
Waqtiga joogtada ah ee Hoosada
Qoraal la daabacay oo ku saabsan arrin 2013 ee Genome Biology ayaa tilmaamaya sida habka kiimikada dabiiciga ah ee ku dhaca gudaha unugyada loo isticmaali karo nooc ka mid ah jadwalka ama qiyaasta sida ugu dhakhsaha badan ee unugta gaboobay.
Nidaamkan, oo loo yaqaano methylation, wuxuu bedelaa DNA - qaababka unugyada unugyada ee unugyada - qaabka la xidhiidha da'da hore.
Cilmi-baaris ka hor Jaamacadda California ee Los Angeles (UCLA) waxay isticmaashay shaybaarada candhuufta laga bilaabo 34-ka mid ah laba mataano oo isku mid ah si ay u muujiyaan meelihii DNA-ku ku xirnayd methylation ku habboon da'da maadooyinka. Cilmi-baarayaasha ayaa markaa tijaabiyay heerarka methylation ee dadweynaha ballaaran waxayna awoodeen inay ogaadaan da'da qaangaarka ah ee da'doodu tahay shan sano gudahood, iyaga oo isticmaalaya kaliya candhuufta qofka.
Steve Horvath, UCLA bini-aadanka bini-aadamka iyo bare-cilmiga bini-aadamka, ayaa cilmibaadhistan ka qaaday baadhitaan dheeri ah oo baadhay in ka badan 8,000 oo unugyo iyo shaybaarrada ay ku deeqeen akhristayaasha kale. Shaybaarka bini-aadamka ayaa laga soo qaaday da'da dhalashada ilaa da'da 101 sano, in ka badan 50 nooc oo unugyo ah iyo unugyo kala duwan qaybaha jidhka, oo ay ku jiraan beerka, kelyaha, maskaxda, sanbabada, iyo wadnaha. Heerarka methyl DNA wuxuu abuuray qaab isku mid ah sida unugyada kala duwan ee gaboobay.
Horvath iyo asxaabtiisuba waxay isticmaaleen qiyaasta si ay u qiimeeyaan heerka da'da 6,000 oo ah noocyo kansar kala duwan, oo ka dhigan 20 nooc oo cudur ah.
Qaybaha kala duwan ee Da'da jirka ee Sicirada kala duwan
Kooxda Horvath waxay ogaadeen in unugyada badankoodu ay si siman u la siman yihiin; Dhaqan ahaan, da'dooda bayoolaji ahaaneed , sida fiican ee ay u shaqeynayaan, waxay ku habboon yihiin da'dooda taariikheed ee taariikheed , sida tirada sanadka ee ku qoran jadwalka.
Si kastaba ha ahaatee, unugyada naaska, waxay ahayd mid ka reeban. Nudaha naasaha leh ee caafimaad qaba ayaa si deg-deg ah u dhaqma oo soconaya laba illaa saddex sano oo ka weyn inta ka dhiman jirka haweeneyda. Tani waxay sharxi kartaa sababta kansarka naasku yahay nooca ugu badan ee kansarka ku dhaca dumarka tan iyo da'da waa cilladda halista iyo nudaha si degdeg ah u sii kordhaya, sidaas darteed, waxay noqon kartaa mid u nugul kansarka.
Dumarka horey u qabay kansarka naasaha, da'da dardargelinta ayaa xitaa aad u badan. Baaritaanka unugyada kudhaca burooyinka kansarka naasaha, cilmi baarayaashu waxay ogaadeen in ay ahayd mid dhexdhexaad ah 12 sano ka weyn inta ka dhiman jirka.
Miyir-beelka degdega ah ee Kansarka ah ee Kansarka ah
Cudurka kansarka waxaa lagu ogaadey in uu ka weyn yahay nudaha caafimaad ee laga helay meelo kale oo jidhka ah. Kooxda cilmi baarista waxay barataa in ka badan 20 nooc oo kansar ah waxaana laga helaa calaamado joogto ah oo gaboobay oo tiradoodu aad u sarreyso. Xaqiiqdii, unugyada kansarka waxay ahaayeen celcelis ahaan 36 sano oo ka weyn jirka intiisa kale.
Tani waxay dhalinaysaa su "aal muhiim ah: Miyay unugyada sii kordhaya u dhaqso badan u nugul kansarka ama unugyada jirada kansarka si dhakhso ah? Horvath wuxuu sharxayaa in labadan waxyaaloodba ay yihiin kuwo run ah. Tusaale ahaan, xaaladaha kansarka badankood, nudaha kuxiga ah wuxuu u muuqdaa mid da 'yar, ama ugu yaraan da'da dhabta ah ee dadka ay ka soo jeedaan, taas oo soo jeedinaysa kansar lafteeda da'da.
Xaqiiqada ah in xitaa nudaha naaska caafimaadku u muuqdo mid weyn marka loo eego heerarka methylation marka la barbar dhigo inta ka dhiman jirka haweeneyda waxay muujineysaa in unugyada sii kordhaya ee sii kordhaya ay u nugul yihiin kansarka.
"Daraasado dheeraad ah ayaa loo baahan doonaa si loo tijaabiyo sharafkan," Horvath ayaa sidaas yidhi. "Waxaan dhab ahaan dooneynaa inaan cabirno da'da nudaha naasaha, aan lahayn kansarka naasaha ee dumarka ah, intaa dheer, waxaannu dooneynaa inaanu tijaabino haddii dardargelinta da'da ah ee nudaha naasku ay saadaalisay horumarinta kansarka mar dambe."
Baaritaanno dheeraad ah oo ku saabsan nudaha naaska caafimaad qaba marxaladaha kala duwan ee nolosha haweeneyda - qaangaadhka, qaangaarka dambe, kadib uurka iyo ka dib markaad uur leedahay - waxay kaa caawineysaa in aad caddeeysid in unugyada naasaha ee si dhaqsi ah u dhaqsaha badan, xaqiiqda, ay u badan tahay in la horumariyo kansarka.
Haddii ay sidaas tahay, tijaabinta heerka methylation ee naasaha ku jira naasaha ayaa hal maalin ku muujin kara fursadda dumarka ee ah inuu ku dhaco cudurkan halista ah.
Telomereska
Telomeriyadu waxay bixiyaan qaab kale si loo cabbiro heerka gabowga. Telomerisku waa qaabab yaryar oo u riixaya walxaha hiddo-ku-wareegsan gudaha qolka maadama uu unuggu diyaar u yahay inuu kala qaybiyo. Mar kasta oo kala qaybsanaanta qaybta unugyada, telomeriyadu way yar yihiin; marka ay aad u gaaban yihiin, unuggu mar dambe ma kala qaybin karo, taasoo keenta dhimashada unugyada.
Waxaa jira cilmi-baaris oo loo socdo si loo cabbiro dhererka telomereedka iyada oo ah nooc ka mid ah saadaalinta ujeedada sida unugyada jirka ee jirkaagu uu gaboobay. Intaa waxaa dheer, saynisyahannadu waxay baarayaan in haysashada telomeriyeyaashu sii dheeraan karaan unugyada yaryar oo si habboon u qaybsanaya.
Ilaha:
Methylation. Waaxda Maraykanka ee Kansarka Qaranka ee Qaamuuska Kansarka. La qabsaday October 25, 2013.
http://www.cancer.gov/dictionary?cdrid=655031
Steve Horvath. "Da'da methyl DNA da'da unugyada aadanaha iyo noocyada unugyada." Genome Biology 2013, 14: R115.
http://genomebiology.com/2013/14/10/R115
Sven Bocklandt, Wen Lin, Mary E. Sehl, Francisco J. Sánchez, Janet S. Sinsheimer, Steve Horvath, iyo Eric Vilain. "Epigenetic Predictor of Age." QALABKA 6 (6): e14821.
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0014821