Correlations of repetitive and AT-rich DNA segments within the chicken globin gene domains.

The repetitive DNA segments were mapped within a 30 Kbp genomic domain including (in 5' to 3' order) the chicken embryonic pi and adult alpha D (minor) and alpha A (major) globin genes. Two repeats map 5 and 8 Kbp upstream from the embryonic pi gene and another 3 Kbp downstream of the adult alpha A gene. These repetitive DNA sequences are placed within, or immediately adjacent to the AT-rich DNA segments framing this domain. Similar correlations exist also within the chicken beta globin gene domain. The positions of these AT-rich and repetitive DNA segments framing the alpha globin gene domain also correlate with other already explored features of long range DNA organisation, as clusters of sites of DNAse I hypersensitivity and differential methylation, sites of Matrix-DNA attachment, and with the beginning and end of the transcribed domain.