Tsarin gadon dabi’u da Siffofin Halitta (3)

Asali da Bunkasa Duk da cewa bincike na hakika a tsarin binciken kimiyya na zamani kan wannan fannin ilmi bai shige shekaru ashirin da wani abu ba, sai dai idan muka yi la’akari da tsarin zamantakewar dan adam a wannan duniya, dangane da tarihi, za mu samu shi ma tsohon fannin ilmi ne kamar sauran […]

Asali da Bunkasa

Duk da cewa bincike na hakika a tsarin binciken kimiyya na zamani kan wannan fannin ilmi bai shige shekaru ashirin da wani abu ba, sai dai idan muka yi la’akari da tsarin zamantakewar dan adam a wannan duniya, dangane da tarihi, za mu samu shi ma tsohon fannin ilmi ne kamar sauran nau’ukan ilmin da suka danganci rayuwar dan adam.  Don haka idan ana maganar asali, a iya cewa lallai ilimi ne mai asali tun farkon samuwar halitta a doron kasa. Wannan a fili yake kamar yadda mu ka gani a misalan da suka zo cikin hadisan da suka gabata a Mukaddima. To amma shahararsa da bunkasarsa ba su kunno kai ba sai cikin ‘yan shekarun baya. Kafin wannan lokaci da muke ciki, akwai wasu marhaloli hudu shahararru da wannan fanni na ilimi ya ketare. 

Marhala ta Farko

Kafin bayyanar tsarin binciken ilimin kimiyya irin na zamani, fannin Tsarin Gadon dabi’u da Siffofin Halitta yana nan, kuma galibi mutane kan bambance dangantakar da ke tsakanin mutane ne ta hanyar dabi’un halitta na bayyane, watau kamar yanayin kirar jiki, da tsawo, da launin idanu, da launin gashin kai, da dai sauransu. Amma a kimiyyance babu wasu abubuwa da ake iya tantance ingancin tabbacin wannan alaka. A cikin wannan marhala ta rayuwar dan adam dai abin da aka dauka shi ne, mutane kan gaji dabi’un halitta ne daga iyayensu, ko danginsu, gaba daya, ba tare da wani kwange ba.  Ma’ana duk Uba ko Uwa, suna gadar wa ‘ya’ya dukkan dabi’un halittarsu ne baki daya, babu kwange. Wannan tsarin tunani, a binciken ilimin dabi’un halitta na zamani, shi ake kira “The Law of Blending Inheritance.” Watau ka’idar da ke nuna cewa dukkan halitta kan gadar wa zuriyarsu cikakken jerin dabi’ar halittar da suke da su ne. Ma’ana suna sajewa da su babu wani bambanci ko kadan. To amma da tafiya ta yi nisa a karni na 19 (19th Century), sai wata sabuwar mahanga mai dalili sama da wadda ta gabaceta ta bullo.

Marhala ta Biyu

A marhala ta biyu ne aka samu wata sabuwar mahanga dangane da abin da ya shafi tsarin gadon dabi’un halitta. Wannan mahanga kuwa ta samo asali ne daga wani shahararren malami mai suna Gregor Mendel dan kasar Jamus, wanda ya gudanar da bincike kan nau’ukan shuke-shuke da yadda ake samun gadon dabi’u a tsakaninsu sanadiyyar “hadin-aure” da ya yi a tsakaninsu, watau “Hybridization” kenan. Ya yi gwaje-gwaje cikin shekarar 1865 inda ya fitar da sakamakon da ke nuna cewa, akan samu gabon dabi’un halitta a tsakanin jinsi da nau’ukan shuke-shuke, amma ba wai cikakkiyar gado ake samu ba, sabanin ra’ayin marhalar farko da ya gabata mai suna “Blending Inheritance.” Wannan ra’ayi na Gregor Mendel shi ake kira da: “Mendelian Inheritance.” A wasu lokuta kuma akan kira shi da suna: “Mendlism.” A cikin wannan marhala ne har wa yau aka fara kiran wannan fanni da suna “Genetics.” Wanda ya fara kiran wannan fanni da wannan suna kuwa shi ne William Bateson, a cikin wata kasidarsa da ya gabatar a wani taron duniya da aka yi a birnin Landan kan “hadin-aure” tsakanin shuke-shuke, watau 3rd International Conference on Plant Hybridization, cikin shekarar 1906. A wannan marhala, abin da tsarin bincike ya tabbatar na tsarin gadon dabi’un halitta duk a kan shuke-shuke ne, ba a gudanar da wani bincike na musamman ba kan kwayoyin halittar dan adam, dangane da abin da ya shafi fannin. A halin yanzu wannan shi ne bangaren nau’in ilimin gadon dabi’un halitta da ake kira; “Classical Genetics.”

Marhala ta Uku

A shekarar 1911 kuma sai bincike kan bangaren kwayar halittar dake dauke da dabi’un halitta ya kunno kai. Wanda ya fara bincike kan wannan fanni kuwa shi ne Thomas Hunt, inda ya gano cewa lallai bangaren Ma’adanar dabi’ar Halitta (Chromosome) ce ke dauke da wadannan dabi’un halitta masu haddasa gadon dabi’un halitta a tsakanin halittu masu rai. A shekarar 1913 kuma bayan shudewar Thomas Hunt, sai wani dalibinsa mai suna Alfred Sturtebant ya tabbatar da cewa lallai dabi’un Halitta (Genes) suna tsare ne, daya na bin daya, a jere a cikin wannan bangare na Ma’adanar dabi’ar Halitta (Chromosome), ba wai a cakude suke ba ko a hargitse. Bayan wannan hobbasa da Thomas da dalibinsa Alfred suka  yi, sai kuma wata muhawara ta kunno kai, cewa: tunda dabi’un Halitta (Genes) ne ke taimakawa wajen samar da Sinadaran kara Kuzari (Cell Protein) ga kwayar Halitta (Cell), shin, tsakanin wannan sinadaran karin kuzari da Ma’adanar dabi’ar Halitta (Chromosome), wanne ne daga cikinsu ke haddasa Gadon dabi’un Halitta a tsakanin halittu masu rai?

Wanda ya fara kokarin gano hakan kuwa shi ne Frederick Griffith a cikin shekarar 1928. Sakamakon bincikensa ya gano masa wani tsarin juyin yanayin da ke faruwa a cikin Ma’adanar dabi’ar Halitta (Chromosome) ne. Wannan tsarin juyin yanayi, wanda Frederick ya kira da suna: “Transformation”, wani mataki ne daga cikin matakan da ke samuwa kafin Gadon dabi’un Halitta (Inheritance) ya samu a cikin kwayar Halitta (Cell). Da aka shiga shekarar 1944 kuma sai wani gungun masana su uku, wato: Oswald Theodore Abery, da Colin McLeod, da kuma Maclyn Mc-Carthy suka gudanar da bincike don tantance hakikanin abin da ke haddasa wannan tsarin juyin yanayi da Frederick ya kira “Transformation” a baya. Sakamakon bincikensu dai ya nuna cewa, Madaukan dabi’ar Halitta (DNA) ne ke haddasa wannan yanayi, wanda mataki ne da ke samar da Gadon dabi’ar Halitta (Inheritance) a tsakanin halittu. Ba su kadai ba, hatta gwajin bincike na musamman da Harshey da Chase suka gudanar a shekarar 1952 ya sake tabbatar da hakan.  

A nasu bangaren kuma, masana James D. Watson da Francis Crick sun gudanar da bincike na musamman kan wannan Madaukan dabi’ar Halitta (DNA), inda suka gano tsarinsa da cikakkiyar siffarsa.  Wannan bincike nasu sun gudanar da shi ne a shekarar 1953. A cikin shekarar 1955 kuma aka sake gudanar da wani bincike kan Madaukan dabi’ar Halitta (DNA), inda aka gano tasirinsa wajen samar da Sinadaran kara Kuzari (Protein), wanda ke taimakawa wajen gina Tambarin dabi’ar Halitta (Genetic Code) na kowane halitta.  Wadannan su ne al’amura muhimmai da suka faru a marhala ta uku cikin wannan fanni na ilimin Tsarin Gadon dabi’un Halitta (Genetics).

Marhala ta Hudu

Marhala ta hudu, wadda ke cike da ci gaba a fannin kimiyya da kere-kere, ita ce marhala ta karshe da wannan fanni na tsarin Gadon dabi’un Halitta ya kutsa. Wannan marhala ta faro ne cikin shekarar 1977, lokacin da wani masani mai suna Frederick Sanger ya gudanar da bincike na musamman kan yadda Madaukan dabi’ar Halitta (DNA) ke jera dabi’un Halitta (Genes) a kwayar halittar rayuka. Sakamakon wannan bincike, wanda Malaman kimiyya ke kira: “DNA Sekuencing,” yana da muhimmanci matuka a wannan fanni na ilimi.  

Bayan sakamakon wannan bincike, a shekarar 1983 kuma sai ga Kary Banks Mullis, wani masani ne kan wannan fanni, inda bayan tsawon lokaci yana gudanar da bincike ya fitar da sakamako kan yadda ake iya tsame sinadarin Madaukan dabi’ar Halitta (DNA) daga sauran sinadaran da ke mahallin Ma’adanar dabi’ar Halitta (Chromosome).  Wannan wani mataki ne da ya samar da karin sanayya kan dabi’un Halitta (Genes). Wannan sabon tsari da Kary Banks ya bankado shi ake kira “Polymerase Chain Reaction,” (PCR). Daga nan aka ci gaba da gudanar da bincike na kwakwaf cikin wannan fanni, ta hanyar amfani da sababbin na’urorin binciken kimiyya da fasahar sadarwa da kere-kere, wajen gano wasu al’amura da suka buya a lokutan binciken shekarun baya. Babban hobbasa da aka yi wajen tantance matakin da ake ganin shi ne na karshe wajen bunkasa wannan fanni shi ne sakamakon binciken da ya tabbata a shekarar 2003, shekarar da aka kammala bincike kan adadin dabi’un Halitta da ke cikin kwayoyin halittar jinsin dan adam baki daya. 

Wannan aikin bincike na musamman wanda aka masa suna THE HUMAN GENOME PROJECT, hukumar Kiwon Lafiyar kasar Amuka da Kamfanin Binciken dabi’un Halitta mai suna Celera Genomics ne suka dauki nauyin aiwatar da shi. A sakamakon binciken ne aka tantance cewa jinsin dan adam na dauke ne da adadin dabi’un Halitta (Genes) tsakanin dubu 20 zuwa dubu 25. Har wa yau sakamakon binciken ya dada tabbatar da cewa, lallai fahimtar yadda wadannan dabi’un Halitta ke jituwa ko kasa jituwa a tsakaninsu ne zai taimaka wajen samar da waraka ga cututtukan da ke addabar al’ummar duniya baki daya. Wannan hobbasa ne ya fitar da abin da na kira: “Taswirar Tambarin dabi’ar Halitta,” wato “The Human Genome.”

Wadannan su ne shahararrun marhaloli hudu masu muhimmanci da wannan fannin ilimi ya kutso ta cikinsu. Duk wani abin da ya danganci wannan fannin ilimi da ba a ambace shi ba, to, ya samo asali ne daga gare su.