Nevertheless all cocoa beans came from the same plant species known as Theobroma cacao, this species has many varieties around the world and each variety has its own genetic pool. Thus, a variety can be differentiated from another one due to the characteristics expressed by their own genes.
Aiming for large scale business models, such as bulk cocoa, governmental agricultural organizations in cocoa countries encourage farmers to grow several varieties in the same plot. Some of the reasons are to reduce pests and diseases, and to spark particular characteristics of the bean, i.e., fat content, climate tolerance, yield, flavour and so on.
So farmers have been trained to cultivate simultaneously at least 5 varieties. Then, when harvesting, varieties are mixed together and after-harvest processed. The result is a blend of dry cocoa beans that one commonly finds when sourcing cocoa beans.
In the case of fine flavor cocoa, aiming to obtain the natural expression of the "terroir" despite of its yields, fat content and vulnerability to plant diseases, only less than 5% of the farmers commits to cultivate only one variety of cocoa bean in its land. Therefore, scarce plots of one specific genetic pool are cultivated in cases such as heirloom, origin or regional cocoa unique varieties. This is what a single genetic cocoa bean is.