It contains 15 exons, including an exon defined by an anaplastic oligodendroglioma expressed sequence tag, and spans at least 61.7 kilobases. hUlip lacks sequences corresponding to the first six exons found in unc-33. unc-33 exons correspond to homologous hUlip exons as follows: VII to 1 and 2, VIII to 3-9, IX to 10-12, and X to 13 and 14.