而是通過選擇性雜交實現的。雖然基因有改變，請不要把這個東西叫做轉基因，因為轉基因是專指特殊的基因工程技術。
下麵是相關的一段英文文章：
Hybridized Wheat May Be To Blame
That doesn't mean wheat hasn't changed over the last half-dozen decades, though—it has, as the result of a process called hybridization (which is different from genetic engineering). And some scientists (although not all) say those changes could be one cause of an increase in the number of people who have an inability to tolerate gluten.
In hybridization, scientists don't tinker directly with the plant's genome. Instead, they choose particular strains of a plant with desirable characteristics and breed them to reinforce those characteristics. When this is done repeatedly, successive generations of a particular plant can look very different from the plant's ancestors.
That's what's happened with modern wheat, which is shorter, browner, and far higher-yielding than wheat crops were 100 years ago. Dwarf wheat and semi-dwarf wheat crops have replaced their taller cousins, and these wheat strains require less time and less fertilizer to produce a robust crop of wheat berries.
Dr. William Davis, author of the anti-wheat best-selling book Wheat Belly, raises questions in his book about whether these changes in wheat have caused the spike in gluten-related health problems, including obesity and diabetes. "Small changes in wheat protein structure can spell the difference between a devastating immune response to wheat protein versus no immune response at all," Davis writes. Modern wheat has been bred to contain more gluten, he says.
However, a study published in the Journal of Agricultural and Food Chemistry cast doubt on part of Davis' hypothesis when it reported that there's not really any more gluten in modern wheat than there was in 1920s-era wheat.
