Molecular organisation of the avian genome

The genome of the domestic fowl comprises about 70% unique sequence DNA and 30% moderate and highly repetitive sequences (see Section 8.2) the question is how are these sequences organised on the 

39 pairs of chromosomes. Various methods have been useful in probing the organisation of the DNA on the chromosomes. In eukaryotes, there is not very much variation in the total GC content of the DNA from different species. It generally ranges between 

Bemardi et al. (1985) have made extensive studies of the genomes of a wide range of eukaryotes using this method. Before carrying out the CsCl density gradient centrifugation they reduced the average 

The repeated DNA sequences may be arranged either in clusters or in a dispersed fashion throughout the genome. The percentage of GC present in 

This repeated element was called Alu because it contains the sequence AGCT that is recognised by the restriction enzyme A/ I. The function of the sequence is not clear. 

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