A susceptibility locus for human systemic lupus erythematosus (hSLE1) on chromosome 2q

To identify chromosomal regions containing susceptibility loci for systemic lupus erythematosus (SLE), we performed genome scans in families with mult iple SLE patients from Iceland, a geographical and genetic isolate, and fro m Sweden. A number of chromosomal regions showed maximum lod scores (Z) ind icating possible linkage to SLE in both the Icelandic and Swedish families. In the Icelandic families, five regions showed lod scores greater than 2.0 , three of which (4p15-13, Z=3.20; 9p22, Z=2.27; 19q13, Z=2.06) are homolog ous to the murine regions containing the lmb2, sle2 and sle3 loci, respecti vely. The fourth region is located on 19p13 (D19S247, Z=2.58) and the fifth on 2q37 (D2S125, Z=2.06). Only two regions showed lod scores above 2.0 in the Swedish families: on chromosome 2q11 (D2S436, Z=2.13) and 2q37 (D2S125, Z=2.18). The combination of both family sets gave a highly significant lod score at D2S125 of Z=4.24 in favor of linkage for;2q37. This region repres ents a new locus for SLE. Our results underscore the importance of studying well-defined populations for genetic analysis of complex diseases such as SLE. (C) 2000 Academic Press.