Blue Rose FlowersWiki info
The genetic engineering involved three alterations — adding two genes, and interfering with another. First, the researchers inserted a gene for the blue plant pigment delphinidin cloned from the pansy into a purplish-red Old Garden rose "Cardinal de Richelieu", resulting in a dark burgundy rose. The researchers then used RNA interference (RNAi) technology to depress all other color production by endogenous genes by blocking a crucial protein in color production, called dihydroflavonol 4-reductase (DFR), and adding a variant of that protein that would not be blocked by the RNAi but that would allow the color of the delphinidin to show. If the strategy worked perfectly, in theory it could produce a truly blue rose. However, the RNAi did not completely knock out the activity of DFR, so the resulting flower still made some of its natural color, and so was a red-tinged blue – a mauve or lavender. Additionally, rose petals are more acidic than pansy petals, and the pansy delphinidin in the transgenic roses is degraded by the acidity in the rose petals. Further deepening the blue colour would therefore require further modifications, by traditional breeding or further genetic engineering, to make the rose less acidic.