A controversial study that showed genetically engineered golden rice could alleviate vitamin A deficiency in children was retracted by the American Journal of Clinical Nutrition on 29 July, nearly 2 years after investigations found problems with how the study had been conducted. Supporters of golden rice are dismayed by the outcome, first reported by Retraction Watch, but they point out that the data and conclusions remain robust.

Vitamin A deficiency is a major health problem in the developing world, causing blindness and impairing the immune system, particularly in children. Golden rice was first developed in the 1990s as a way to supplement diets lacking in vitamin A. Researchers added genes to allow rice to make beta-carotene, a precursor molecule for vitamin A synthesis. In 2008, Guangwen Tang of Tufts University organized a nutritional trial of golden rice. Working with colleagues in China, the researchers gave golden rice, spinach, or a supplement to 68 children aged 6 to 8 in Hunan province.

The findings, published in 2012, showed that the beta-carotene in golden rice was just as effective at alleviating vitamin A deficiency in children. A single serving of 100 to 150 grams of golden rice could provide about 60% of the daily requirement of vitamin A. The paper is one of several cited by IRRI, the nonprofit rice research institute in the Philippines, as support for the potential of golden rice.

Shortly after the paper was published, Greenpeace claimed that the children had been used as “guinea pigs.” Media outrage in China exploded, and Tufts began inquiries by internal and external panels. In September 2013, the panels reported multiple irregularities; for example, several consent forms had been received after the trial began. (The panels also concluded that the study had been safe and its conclusions valid.) The university announced it would bar Tang from working with human subjects for 2 years.

Last year, Tang asked the Massachusetts Superior Court to stop the American Journal of Clinical Nutrition from retracting the article, arguing it would constitute defamation. Judge Kenneth Salinger denied the petition on 17 July and the journal proceeded to retract the study, citing insufficient evidence for approval by an ethics committee in China and consent forms from all participants.

Tang did not reply to a request for comment, but Adrian Dubock, executive secretary of the Golden Rice Humanitarian Board in Switzerland disputes that there were any ethical irregularities and argues that the retraction is not warranted. He says it’s too soon to assess the impact of the retraction on political support for golden rice. “This is a low point, but I think it’s recoverable.” Tang and her co-authors could resubmit the paper elsewhere, and Dubock says this option had been discussed earlier. “I think they will,” he says.