Methylation of a middle repetitive DNA sequence class during differentiation in Friend erythroleukemia cells

Abstract
We have examined the methylation patterns within middle repetitive sequences in Friend erythroleukemia cells. Mouse‐interspersed‐family‐1 (MIF‐1) and a group characterized by a 1350‐bp Eco‐Bam fragment cloned into pBR322 as plasmid pFS‐13, are both less modified in Friend cell DNA than in normal tissue DNA. The pattern of methylation present in pFS‐13 homologous sequences was found to be stable during cell division, i.e., somatically inherited, and stable during differentiation induced by HMBA.