Comparative mapping of the human homologue of the rat diabetes susceptibility gene lyp to a 1.3-Mb segment on HSA7.

The rat diabetes susceptibility gene, Lyp or Lymphopenia, has been localized to RNO4. Proximal to Lyp are the genes caspase-2 (Casp2) and pancreatic trypsin 1 (Prss1), while neuropeptide Y (Npy) is the closest distally positioned gene. In human, the three genes are syntenic on HSA7, but they are not on a conserved segment: CASP2 and PRSS1 are localized to 7q35, while NPY is localized to 7p15.1. This raises the question whether the human homologue of Lyp is linked to CASP2/PRSS1 or to NPY. We present a comparative map of the Lyp region in rat and human, assigning the gene to a 1.3-Mb segment between RNY3 and ABP1 at 7q35.