generator that takes into account the predilection given to certain bases in the region under comparison. For example, when a sequence of one million bases from the human genome was compared with that from a randomly generated sequence, the percentage of A, T, G and C within that human sequence was computed, and the random base generator was modified to adjust the weights of these bases while generating them. Corresponding methodologies were used for plotting the frequencies of ARFs (lengths between any three amino-acid codons) from a genome or random sequence. Comparative studies also included random sequences that were generated based on the di-nucleotide composition of a given genome. All plots were drawn with KaleidaGraph 4.02 from Synergy Software. Programs were written in Perl with considerable usage of Bioperl modules. Exons and Spliced Genes Only coding sequences were used for computing the lengths of exons and for simulated splicing. 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Bhasi A, Pandey RV, Utharasamy SP, Senapathy P (2007) EuSplice: a unified resource for the analysis of splice signals and alternative splicing in eukaryotic genes. Bioinformatics 23: 1815–23. PLoS ONE | www.plosone.org 11 October 2008 | Volume 3 | Issue 10 | e3456