Affiliations: Nanyang Centre for Supercomputing and Visualisation,
N3-2c-113b, 50 Nanyang Avenue, Nanyang technological University, Singapore.
Tel.: +65 6 790 5836; Fax: +65 6 791 1859 | Human Genome Laboratory, Department of Microbiology,
Faculty of Medicine, National University of Singapore, Kent Ridge, Singapore.
E-mail: [email protected]
Note: [] Corresponding author
Abstract: The human genome is revisited using exon and intron distribution
profiles. The 26,564 annotated genes in the human genome (build October, 2003)
contain 233,785 exons and 207,344 introns. On average, there are 8.8 exons and
7.8 introns per gene. About 80% of the exons on each chromosome are < 200 bp
in length. < 0.01% of the introns are < 20 bp in length and < 10% of
introns are more than 11,000 bp in length. These results suggest constraints on
the splicing machinery to splice out very long or very short introns and
provide insight to optimal intron length selection. Interestingly, the total
length in introns and intergenic DNA on each chromosome is significantly
correlated to the determined chromosome size with a coefficient of correlation
r = 0.95 and r = 0.97, respectively. These results suggest their implication in
genome design.
