Ubusanzwe ubwoko bw’amaraso ni O, A, B na AB. ubu bwoko bushobora kuba ‘negatif’ cyangwa ‘positif’ bitewe n’ibibugize ari byo bita ‘antigenes’ na ‘antibodies’.

Ubushakashatsi bwakozwe n’umunyabwenge Prof. Furukawa Takeji wo mu Buyapani mu mwaka wa 1927, bugaragaza ko ubwoko bw’amaraso bwerekana uko umuntu ateye, imitekerereze ye n’uko yiyumva.

Ibi byaje no gutuma mu gihugu cy’u Buyapani guhera mu mwaka wa 1931 kugeza magingo aya, batanga akazi bagendeye no ku bwoko bw’amaraso y’uwo bagiye kugaha, kuko bizera ko bigira ingaruka mu kuba yagakora neza cyangwa akakica.

Ubushakashatsi bwa Prof. Furukawa bwagaragaje ko abantu bafite amaraso yo mu bwoko bwa ‘‘A’’ bakunze kuba abahanga bakanagira umutima mwiza, bikaba ikinyuranyo ku bafite amaraso yo mu bwoko bwa ‘‘B’’.

Abafite amaraso yo mu bwoko bwa ‘‘O’’ bo bafatwa nk’abantu bagira amatsiko cyane, abanyabuntu ndetse n’abantu bahagarara kucyo bemera ntibahindurwe n’abandi.

Ubu bushakashatsi kandi bugaragaza ko abafite amaraso yo mu bwoko bwa ‘‘AB’’ baba nk’abanyabugeni ariko bikaba bigoye gukorana na bo kuko batumvikana, ndetse bikanagorana kubamenya kuko bahindagurika.

Ikinyamakuru Japan Experience cyatangaje ko ibi byatumye muri icyo gihugu hakwirakwira imvugo ivuga ngo ‘‘Mu Buyapani, icyo uri cyo kigenwa n’amaraso uva.’’

Mu gihe hari abaturage bo mu bihugu bitandukanye batita ku kumenya ubwoko bw’amaraso bafite, mu gihugu cy’u Buyapani ho babiha agaciro gakomeye kuko 90% by’abagituye baba bazi ubwoko bw’amaraso bafite.

Ntibabumenya gusa kuko bigira ingaruka mu itangwa ry’akazi, ahubwo babikora kuko binafasha mu gutanga cyangwa guhabwa ubutabazi bwihuse, mu gihe umuntu agize uburwayi cyangwa impanuka ishobora gutuma ahabwa cyangwa atanga amaraso.

Imibare yo muri 2012 igaragaza ko 40% bya miliyoni zisaga 125 zituye u Buyapani bafite amaraso yo mu bwoko bwa A, 30% bakagira O, 20% bakagira B, naho abasigaye bakagira 10%.

Mu ntambara ya kabiri y’Isi, bivugwa ko u Buyapani bwakoze amatsinda mu basirikare bacyo hagendewe ku bwoko bw’amaraso bafite, kuko bari bizeye ko buri muntu ashobora gutanga umusaruro ku rugamba bitewe n’ubwoko bw’amaraso afite.

BBC itangaza ko n’ubwo ibi bifatwa gutya mu gihugu cy’u Buyapani, bamwe mu bandi bahanga muri siyansi batanze ibitekerezo kuri ubu bushakashatsi bavuga ko batemeranywa nabwo, ko ibi ari ibisanzwe kuba sosiyete y’abantu runaka yagira ibyo yizera bitewe n’intego yayo , bikaba byaba impamvu yo guca amatsinda mu bantu kugira ngo ibyo bashaka bikorwe neza.

Ubushakashatsi bugaragaza ko ubwoko bw'amaraso bushobora kugena imyitwarire y'umuntu