Control of accidental gene escape

UniCrop develops novel molecular approaches to eliminate the accidental gene flow from transgenic plants to wild and cultivated relatives through two systems:

1) Recoverable Block of Function (RBF) and
2) Repressed Excision System (RES).


RBF consists of a Blocking construct (BC) linked to the transgene of interest (TGI) and a Recovering construct (RC). Figure 1.


The Blocking construct blocks a certain molecular or physiological function of the host plant causing the death or sterility of the host plant in natural conditions. The Recovering construct, when artificially induced, prevents the blocked function, and thus the host plant produces viable fertile offspring.(WO 02/06498).

RES is aimed at removing the transgenic insert, causing the transgenic plant to produce non-transgenic seeds in natural conditions.


RES consists of the Excision construct (EC), which completely cuts off the transgenic insert, and the Repressor construct (RC), which represses the expression of the EC. Figure 2 (WO 02/064801).

Double RBF, Intron-inserted BC and RES technologies are priority fields of interest of UniCrop in developing gene escape control methods.


Several molecular models are performed on tobacco plants as shown in Figure 3. The seeds germinate only after the artificial heat treatment (left). In natural environmental conditions the germination is inhibited (right).