Is DNA methylation responsible for mammalian X chromosome inactivation?
MOHANDAS et al. (1981) have proposed that mammalian X chromosome inactivation involves segmental methylation of cytosine residues in the DNA at multiple sites along the X chromosome. Using antibodies specific for 5-methylcytosine, we have found no detectable difference in the extent of methylation of the DNA in the two X chromosomes of owl monkey or human females. Thus inactivation (facultative heterochromatization) of the X chromosome is not due to, or associated with, intense DNA methylation comparable to that seen in most constitutive heterochromatin.
D044503:5-Methylcytosine; D000818:Animals; D003596:Cytosine / Q000031:analogs & derivatives* / Q000502:physiology; D004247:DNA / Q000235:genetics*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007158:Immunologic Techniques; D008745:Methylation; D012730:Sex Chromosomes / Q000502:physiology*; D014960:X Chromosome / Q000502:physiology*
D044503:5-Methylcytosine; D003596:Cytosine; D004247:DNA