^aBackground gene set: (R) RefSeq; (V) Vega; (E) Ensembl; (ext) extended by overlapping cDNA clusters.

^bDoes not overlap known genes.

^cOverlaps gene(s) and extends in 5′ direction.

^dOverlaps gene(s) and extends in 3′ direction.

^eOverlaps gene(s), does not extend, but contributes novel internal exons.

^fAll exons now represented in gene set.