Expression changes of duplicated genes in allotetraploids of Brassica detected by SRAP-cDNA technique

Polyploidization plays an important role in plant evolution, and it may trigger changes in genome structure and gene expression. The purpose of this study was to detect the extent of gene expression alterations in natural Brassica allotetraploids. Sequence-related amplified polymorphism (SRAP)-cDNA display was carried out on six species (13 accessions), three allotetraploids and their three ancestral diploids. Total of 1496 transcripts were screened, finding that 92 (6.1%) transcripts were subjected to silencing in allopolyploids, while 19 (1.3%) transcripts were activated. The results indicated that a significant fraction of duplicated genes have shown expression alterations in the natural allotetraploids compared with their diploid parents.