  The Dissertation is focused on the studies of associations between functional
elements in human genome and their nucleotide structure. The asymmetry in
nucleotide content (skew, bias) was chosen as the main feature for nucleotide
structure. A significant difference in nucleotide content asymmetry was found
for human exons vs. introns. Specifically, exon sequences display bias for
purines (i.e., excess of A and G over C and T), while introns exhibit
keto-amino skew (i.e. excess of G and T over A and C). The extents of these
biases depend upon gene expression patterns. The highest intronic keto-amino
skew is found in the introns of housekeeping genes. In the case of introns,
whose sequences are under weak repair system, the AT->GC and CG->TA
substitutions are preferentially accumulated. A comparative analysis of gene
sequences encoding cytochrome P450 2E1 of Homo sapiens and representative
mammals was done. The cladistic tree on the basis of coding sequences
similarity of the gene Cyp2e1 was constructed. A new programming tools of NCBI
database sequence mining and analysis was developed, resulting in construction
of a own database.
