Chicken lens δ-crystallin gene expression and methylation in several non-lens tissues

RNA sequences coding for the most abundant chicken lens protein, δ-crystallin, were detected at very low levels in day old post atch chick lung, heart, kidney and liver, and in 6 day embryo headless bodies. The pattern of cytosine methylation within the CCGG sequences of the 6-crystallin genes was also examined and shown to vary in several non-lens tissues, from several stages of development. Embryonic neural retina, which expresses a higher level of δ-crystallin RHA than the above tissues, is no less methylated in the sites studied than the tissues which have no association with the eye, and is actually more heavily methylated than the kidney. Thus no obvious correlation was found between undennethylation and gene expression