Beyond specific genes associated with the change from shade to light environment, we also found a significant enrichment of interesting gene ontology terms. The most significant GO terms observed were and oxidoreductase activities associated with NADPH DH complex genes [64, 65]. Whatever the strategy of enrichment test used, the results were robust for these functions. The NADH DH complex is an important set of enzymes for chlororespiration . The NADH DH complex is involved in photosynthesis , more specifically in the photosystems I (PSI) and II (PSII). It plays a role in protection against photo-oxidative stresses associated with the formation of reactive oxygen species (ROS) . High light and heat could favour the production of ROS [69, 70]. In oats, NADH DH is over-expressed with increasing light . Consequently, it has been postulated that this type of complex plays a role in mitigating ROS stress associated with increasing intensity of light or heat. In Brassica plants, the same NADH DH complex has also been reported to be associated with the domestication process . The wild species of Brassica showed higher tolerance to high light and heat intensity than the cultivated species . In this specific case, domestication was associated with a decrease in photosynthetic parameters under stress conditions in the cultivated species . The two wild species of yam are vines that grow in partial shade. The cultivated species D. rotundata grows under full sunlight in the field. We hypothesize that adaptation of the cultivated yam led to the selection of genes that enable efficient photosynthesis with increasing light and heat intensity. Optimizing photosynthesis is also an important way to enhance production of carbohydrate, later stored as starch in the tuber.