Polyploid organisms have more than one genome and carry multiple copies of most genes, a characteristic that can mask genetic mutations and enable polyploid organisms to tolerate induced mutations. In polyploid food crops, such as wheat, the extra gene copies can reduce the probability of selection for favorable recessive mutations during natural or human selection.

To study gene function in polyploid crops, researchers sequenced and catalogued more than 10 million mutations in the protein-coding regions of 2,735 mutant lines of tetraploid and hexaploid wheat— species that carry four or six complete sets of chromosomes.

On average, the authors detected around 2,700 mutations per plant in the tetraploid species and more than 5,300 mutations per plant in the hexaploid species, findings that reflected a count of 35 and 40 mutations per kb in the tetraploid and hexaploid populations, respectively.

Moreover, the authors identified mutations likely to disrupt gene function for more than 90% of the wheat genes in both the tetraploid and hexaploid populations. According to the authors, the results might help explore the function of wheat genes and improve wheat varieties.

http://www.pnas.org/content/early/2017/01/13/1619268114.abstract?sid=34668cda-3bda-40c0-bc8b-ac5f0cf68c81