A program for constructing nucleosome formation potential profile was appli
ed for investigation of exons, introns, and repetitive sequences. The progr
am is available at http: //wwwmgs.bionet.nsc.ru/mgs/programs/recon/. We hav
e demonstrated that introns and repetitive sequences exhibit higher nucleos
ome formation potentials than exons. This fact may be explained by function
al saturation of exons with genetic code, hindering the localization of eff
icient nucleosome positioning sites.