We study statistical properties of DNA chains of thirteen microbial complet
e genomes. We find that the power spectrum of several of the sequences stud
ied flattens off in the low frequency limit. This implies the correlation l
ength in those sequences is much smaller than the entire DNA chain. Consequ
ently, in contradiction with previous studies, we show that the fractal beh
avior of DNA chains does not always prevail through the entire: DNA molecul
e. [S1063-651X(99)10211-3].