A diabetogenic gene, ODB2, identified on chromosome 14 of the OLETF rat and its synergistic action with ODB1

Genetic analysis of diabetogenic genes involved in developing spontaneous diabetes of MDDM type in the OLETF rat was performed in (OLETF female X B N male )F2 and (OLETF female XBN (male)F1 female X OLETF male backcross male offspring. In the F2 and/or backcross offspring, a high frequency of diabetes was found to be associated with a coat color gene, H (hooded). Since it is known that H gene is located on chromosome 14, an attempt was made to examine the linkage association of the gene responsible for elevating plasma glucose with various microsatellite markers of chromosome 14 in male F2 and/or backcross offspring. The results show that a high linkage exists with a microsatellite marker, D14Mit4 (LOD>2). The gene was designated Odb2. It was also found that both genes, Odb1 which was previously found on chromosome X, and homozygous Odb2 are required to cause elevated plasma glucose in OGTT. (C) 1996 Academic Press, Inc.