Figure 1. Mean Intron Length as a Function of Intron Position, Counting from the 5′ End of the Gene.

Intron length was nearly constant for introns 5 to 10. Proximity to the 3′ end of the gene was not correlated with intron length. Error bars show ± twice the standard error. The data shown are for genes with exactly ten introns so that positional effects from the 3′ ends can also be assessed.