The epigenetic diversity of six genotype groups (commercial cultivars, S. officinarum, S. spontaneum, S. robustum, S. barberi, and Erianthus sp.) was assessed through methylation-sensitive amplification polymorphism (MSAP). A total of 1341 MSAP loci were analyzed, of which 1117 (83.29%) were susceptible to cytosine methylation and responsible for a higher proportion of overall diversity among genotypes. The MSAP selective primer combinations captured different proportions of internal and external cytosine methylation loci across genotype groups, while the average external cytosine frequency was higher for all genotype groups. The genotypes were divided into two subpopulations with a high differentiation index (φst = 0.086) based on epigenetic loci. The genotypes were clustered in three subgroups for both methylated and unmethylated loci, considering dissimilarity values. Four methylated fragments (MFs) were randomly selected and subsequently sequenced and compared with sugarcane public databases using BLASTN. MF alignments suggest that cytosine methylation occurs in sugarcane near CpG islands and tandem repeats within transcribed regions and putative cis-regulatory sequences, which assigned functions are associated with stress adaptation. These results provide the first insights about the distribution of this epigenetic mark in sugarcane genome, and suggest a biological relevance of methylated loci.

6个基因型组（商业品种的后生多样性S.良姜，割手密，S.粗壮，S. barberi和蔗通过甲基化敏感性扩增多态性（MSAP）进行评估。总共分析了1341个MSAP位点，其中1117个（83.29％）易受胞嘧啶甲基化的影响，并且在基因型中占整体多样性的比例更高。MSAP选择性引物组合在基因型组中捕获了不同比例的内部和外部胞嘧啶甲基化位点，而所有基因型组的平均外部胞嘧啶频率更高。基因型被分为两个高分化指数（φ）的亚群。st = 0.086）基于表观遗传位点。考虑到不相似值，基因型被聚类为甲基化和未甲基化基因座的三个亚组。随机选择四个甲基化片段（MF），随后进行测序，并使用BLASTN与甘蔗公共数据库进行比较。MF比对表明，胞嘧啶甲基化发生在CpG岛附近的甘蔗中，并且在转录区和推定的顺式调控序列内串联重复，这些功能与胁迫适应有关。这些结果提供了关于该表观遗传标记在甘蔗基因组中分布的初步见解，并暗示了甲基化基因座的生物学相关性。