The pitch of chromatin DNA is reflected in its nucleotide sequence.

A correlation analysis of chromatin DNA nucleotide sequences reveals the clear tendency of some of the dinucleotides to be repeated along the sequences with periods of 3 and about 10.5 bases. This latter period, which is equal within experimental error to recent estimates of the pitch of the DNA double helix Wang, J. (1979) Proc. Natl. Acad. Sci. USA 76, 200-203; Trifonov, E. & Bettecken, T. (1979) Biochemistry 18, 454-456 is interpreted as a reflection of the deformational anisotropy of the DNA molecule that facilitates its smooth folding in chromatin.