November 27, 2006

 

US breakthrough in genetics sows better wheat seed

 

 

The scientists at the University of California, Davis have identified a gene from wild wheat that could increase protein and micronutrient content of its cultivated cousin by 10 to 15 per cent, and could soon be used in food products with enhanced nutritional value.

 

The focus of the study is the gene GPC-B1, found to be non-functional in all the cultivated pasta and bread wheat varieties analysed by the researchers.

 

Through many centuries of domestication by farmers and plant breeders, the researchers found wheat had lost some of the vital protein and minerals, such as iron and zinc that the genes in the ancient wild seeds carried. After cloning the major gene for those nutrients from current wild wheat, the UC Davis scientists have bred them back into new wheat strains without the need for more controversial genetic engineering.

 

The seeds are now ready to be distributed to India, China, Argentina and Canada.

 

To test if the gene could lead to accelerated grain maturity and increased protein and micronutrient content, the researchers used a technique called RNA interference to create GM wheat lines with decreased levels of the GPC gene.

 

The experiment yielded spectacular results, said Professor Jorge Dubcovsky from the University. The resulting grains from the GM plants matured several weeks later than the control plants and showed 30 percent less grain protein, zinc and iron, without differences in grain size. The experiment confirmed that this single gene was responsible for all these changes.

 

Dubcovsky and his team have now been working on introducing the same gene into US wheat varieties through a process called Marker Assisted Selection. The technology allows the researchers to use the genetic information found in the plant's DNA to select those plants that carry desirable traits, such as disease resistance and improved quality.

 

Breeding programmes have earlier used the same gene to develop elite breeding lines, which are close to being released as new wheat varieties.

 

Such varieties are now being tested by breeders in multiple environments to determine if the introduction of GPC-B1 has any negative impacts on factors such as yield and quality.

 

Concerns associated with transgenic crops are not valid with the new wheat variety as the resulting varieties are not genetically modified organisms, likely to speed their commercial adoption, said a statement from the University of California.

 

The new studies reinforced the inherent value of basic research for improving the lives of those youngest among them who remained without a voice in this world, commented Dr Jonathan Gitlin, a paediatrician and geneticist at Washington University in St. Louis on the Davis team's report.