Genetic and epigenetic changes (DNA methylation) were examined in the tissue-culture propagated interspecific potato somatic hybrids between dihaploid Solanum tuberosum and S. pinnatisectum. Amplified fragment length polymorphism (AFLP) and methylation-sensitive amplified polymorphism (MSAP) were applied to detect the genetic and epigenetic changes, respectively in the somatic hybridsmotherplants (1st cycle) and their regenerants (30th cycles sub-cultured).
Results:
To detect genetic changes, eight AFLP primer combinations yielded a total of 329 scorable bands of which 49 bands were polymorphic in both motherplants and regenerants. None of the scorable bands were observed in term of loss of original band of motherplant or gain of novel band in their regenerants. AFLP profiles and their cluster analysis based on the Jaccard’s similarity coefficient revealed 100% genetic similarity among the motherplant and their regenerants. On the other hand, to analyze epigenetic changes, eight MSAP primer pair combinations detected a few DNA methylation patterns in the motherplants (0 to 3.4%) and their regenerants (3.2 to 8.5%). Out of total 2320 MSAP sites in the motherplants, 2287 (98.6%) unmethylated, 21 (0.9%) fully methylated and 12 (0.5%) hemi-methylated, and out of total 2494 MSAP sites in their regenerants, 2357 (94.5%) unmethylated, 79 (3.1%) fully methylated and 58 (2.3%) hemi-methylated sites were amplified.
Conclusion:
The study concluded that no genetic variations were observed among the somatic hybridsmotherplants and their regenerants by eight AFLP markers. However, minimum epigenetic variations among the samples were detected ranged from 0 to 3.4% (motherplants) and 3.2 to 8.5% (regenerants) during the tissueculture process.