NEW DNA TECHNOLOGIES PROVIDE INSIGHTS INTO THE MOLECULAR BASIS OF SOMACLONAL VARIATION IN SUGARCANE

摘要

We have developed efficient DNA marker technologies to assess the nature and extent of genomic change in sugarcane clones. Randomly Amplified DNA Fingerprinting (RAF) is a refinement of earlier technologies and monitors DNA sequence changes, whereas Amplified DNA Methylation Polymorphisms (AMPs) detect DNA methylation changes. These protocols were used to investigate the molecular basis of somaclonal variation in sugarcane. DNA methylation changes were found to be widespread in the genomes of tissueculture derived plants, and a subset of somaclones also showed loss of genomic DNA. Loss of DNA was correlated with loss of yield in a selection of transgenic lines. The DNA marker technologies we have developed could be applied as diagnostic tests to identify tissue culture conditions that minimise genetic change that occurs during the process of genetic engineering.