GM folate rice could help tackle neural tube defects, say researchers

Researchers from the Ghent University in Belgium looked at the impact of the folate rice on folate-deficient rats over a period of 12 weeks.

They said the folate rice – which contained 100 times the folate content of wild rice – alleviated anemia and counteracted hyperhomocysteinemia.

“​Locally grown folate rice could be a valuable asset to reduce the health burden caused by folate deficiency in poor rural regions where other ways of sustained supplementation are difficult to implement.” ​

They said regions like the Shanxi province in China suffered a much higher prevalence of neural tube defects compared to more developed regions – amounting to 60.9 out of 10 000 live births or 38% folate deficient individuals, compared to around 2.9 out of 10 000 live births and less than 10% folate deficient individuals, respectively.

The potential public health impact of this had been investigated in the past, but the biological efficacy of the crop now needed to be demonstrated, something which would be a “pivotal step” ​toward public acceptance. This study therefore aimed to investigate the effectiveness of the rice as a source of folates for organisms.

“All together, we have provided evidence that folates from folate rice are released in the gastrointestinal system following consumption by rats, reach the systemic circulation, are incorporated in red blood cells and are biologically active, as evidenced by folate determination in plasma and red blood cells, the alleviation of anemia and counteraction of pronounced hyperhomocysteinemia. Pending confirmation of these findings in a human trial, locally grown folate rice may serve as a source of folate in regions of the world where traditional fortification techniques are not feasible​,”​ they wrote in the Molecular Nutrition and Food Research ​published paper.

Sufficient results ​

Five groups of 12 rats were given either: a folate-free diet, a wild-type rice naturally meaning an intake of 0.11 μg of folic acid per rat per day, ​fortified rice meaning 3.00 μg of folic acid, fortified rice meaning 3.12 μg or a positive rodent control diet meaning a folate intake of 11.4 to 25.0 μg.

The folate-free and wild rice rats suffered from decreased hematocrit – the volume percentage of red blood cells in blood – and lower folate concentrations in both plasma and red blood cells, leading to either serious risk of or actual death during the trial.

However, the animals receiving the fortified rice or the positive control diet all survived and saw their hematocrit normalised, plasma and red blood cell folate concentrations increased as well as seeing a counteraction of pronounced hyperhomocysteinemia – an abnormally high level of amino acid homocysteine in the blood associated with folate deficiency.

Engineering change ​

The GM rice was engineered from the Nipponbare variety with an increased production of folate building blocks. The rice used contained on average 1563 μg folates per 100 g. 

This was not the first time rice had been proposed as a delivery mechanism for GM-driven nutrition strategies. Researchers developed the so-called GM golden rice - engineered so that the naturally occurring beta-carotene in the plant’s inedible leaves also occurred in its grains - to tackle vitamin A deficiency. This was a topic which has left opinions divided​ and saw field trials destroyed​ in the Philippines. 

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Source: Molecular Nutrition and Food Research​

Published online ahead of print, doi: 10.1002/mnfr.201400590​ ​

“Folates from metabolically engineered rice: A long-term study in rats”​ ​

Authors: F. Kiekens, D. Blancquaert, L. Devisscher, J. Van Daele, V. V. Stove, J. R. Delanghe, D. Van Der Straeten, W. E. Lambert and C. P. Stove