A second-generation genome screen for linkage to type 1 diabetes in a Bedouin Arab family.

IDDM17 on chromosome 10 was identified in an initial genome screen of 13 members (10 affected) of a large Bedouin Arab family that had 19 relatives affected with type I diabetes. Two more children have now been diagnosed with the disease. A second genome screen with 45 members (17 affected members, spouses, and offspring; 312 markers) was performed. A parallel version of GENEHUNTER was used for parametric and nonparametric linkage analyses. The nonparametric linkage analysis (NPL) confirmed the IDDM17 locus (NPL = 3.79; P = 0.001) with a prominent LOD (logarithm of the odds =2.38) peak. These results demonstrate the strong potential of genetically homogenous, extended families for mapping genes that contribute to a complex disease.