Introduction

The GMO Panel assessed maize MON94804 (EFSA, 2024a). This maize is genetically engineered to produce an artificial miRNA intended to selectively suppress two genes within a larger gene family involved in the biosynthetic pathway of gibberellic acid (GA).

The development of the artificial GA20ox_SUP miRNA started initially with miR1425 from rice; mature miRNA was replaced with sequences specific to GA20ox3 and GA20ox5 genes from Zea mays. The miRNA is meant to downregulate the expression of these two genes each of which is known to have several copies in the maize genome.

This significantly reduces the growth of the plants. Compared to the original plants, the genetically engineered (GE) plants are expected to have a height reduction of approximately 1/3, without this having a negative impact on the maize grain yield (normal growth of ears and reproductive tissues).