The development of a genetically modified (GM) rice rich in Vitamin A is seen to be accelerated by a more advanced genetic "transformation event" being donated by plant breeder Syngenta which uses corn (maize) as source of pro-Vitamin A betacarotene.

Dr. Antonio A. Alfonso, plant breeding and biotechnology chief of the Philippine Rice Research Institute (PRRI) , said PRRI is collaborating with the International Rice Research Institute (IRRI) in the development of GM rice fortified with Vitamin A using a transformation event to be donated by Syngenta to the Golden Rice Humanitarian Board (GRHB).

A transformation event involves the transfer of a gene with the desired trait (in this case, betacarotene enrichment) into a plant targeted to be transformed with this desired characteristic.

"Syngenta is donating the transformation event to the Humanitarian Board to IRRI which will share this with us," Alfonso said in an interview.

PRRI and IRRI have earlier been working on GM rice endowed with Vitamin A using a transformation event, also donated by Syngenta, that inserted the gene of Vitamin A rich daffodil into rice.

But the insertion of a daffodil gene into rice will definitely involve more complications in getting approved by the National Committee on Biosafety of the Philippines (NCBP) and the entire Philippine GM regulatory body since daffodil, a flower with yellow petals, is not food.

"The use of maize will hasten regulations because the issue of allergenicity and toxicity will no longer be delved very stringently because daffodil is not being eaten, but maize is food," he said.

What is good about the use of corn gene is it has raised betacarotene level to 37 micrograms (MG) per gram compared to only 1.6 MG per gram betacarotene content in daffodil.

"That's an increase of 23 times," Alfonso said who explained that scientists have shifted to inserting gene with betacarotene gene in rice instead of a gene with Vitamin A since human intake of excessive Vitamin A is known to lead to toxicity.

On the other hand, when taken by human, excess betacarotene is only disposed of by the body rather than poisons it.

"Even if you eat lots and lots of fruits and vegetables with betacarotene, the excess is just eliminated," he said.

With food safety known in corn, Alfonso said the completion of for the GM rice testing, also called "Golden Rice" for its yellow color, may come sooner.

"We already have the F1 progeny, the cross between the popular inbred rice variety and the golden rice. We'll still cross it many times, (but) we project within three years we'll have a stable line (in a contained laboratory)," he said.

Instead of using highyielding hybrid rice varieties (a cross-pollination of two parents with superior characteristics) for the betacarotene enrichment, PRRI will use an inbred (self-pollinating) variety prevalent in Vitamin A deficiency areas.

"The idea is to use inbred so that farmers planting in Vitamin A deficient (VAD) farflung areas in Visayas and Mindanao who only depend on subsistence farming won't need seeds everytime," he said.

Unlike inbred seeds that can be used repeatedly, hybrid seeds are used only once or they lose their yield vigor.

PRRI is specifically crossing the golden rice with inbred PSBRC 82 which yields an already high five metric tons (MT) per hectare.

Since regulatory testing is done in the field, Alfonso said multilocational testings (required in propagating a GM crop) may done simultaneously with regulatory requirements for the commercialization of GM rice after PRRI's development of a stable line in three years.

Alfonso noted though that an important test has to be done on the GM rice-- an efficiency test which determines if this rice will indeed raise Vitamin A level in man.

But this study, he said, may already be undertaken by the GHRB and IRRI rather than by the PRRI.

Alfonso said that it is known that since all living things - plants and animals - have certain common genes, it does not actually matter where the gene will come from for as long as it contains the traits desired. However, he said that genetic engineering experts found that among the betacaroteneendowed gene used, among these were tomato, pepper, daffodil, corn, and another rice variety, corn had the highest betacarotene content.

VAD is said to be inflicting 100 to 200 million children worldwide and is causing one to 2.5 million deaths in preschool children. In the Philippines, VAD is inflicting two in very 10 pregnant and lactating women and four in every 10 children aged six months to five years.