METHYLATION PATTERNS IN THE HUMAN MUSCLE-SPECIFIC ENOLASE GENE (ENO3)

The methylation status in the human-muscle enolase gene (ENO3) was ass ayed. Previous sequence data and MspI cleavage sites indicate the pres ence of a 5' CpG-rich island of at least 4 kb: none of 22 characterize d MspI CCGG sites is methylated in any of muscle, sperm or brain DNA. However a complex pattern of complete and partial methylation of MspI sites that is different between tissues is observed within the ENO3 ge ne: events at one site may be specific to muscle DNA. The absence of m ethylation in the promoter region of the ENO3 gene makes it unlikely t hat methylation plays a causal role either in transcriptional events o r in the divergence of enolase-isogene regulation. The role of tissue- specific methylation events within ENO3 remains to be determined.