SEL1L microsatellite polymorphism in Japanese patients with autoimmune thyroid diseases

The autoimmune thyroid diseases (AITDs), comprising Graves' disease (GD) an d Hashimoto's thyroiditis (HT), appear to develop as a result of complex in teractions between predisposing genes and environmental triggers. A recentl y performed genome-wide linkage study identified six loci that showed evide nce for linkage to AITD. One locus, GD-l, on chromosome 14q31 was mapped to within 2 centimorgans (cM) of the recently reported multinodular goiter (M NG)-1 locus. Furthermore, microsatellite markers for the thyroid stimulatin g hormone receptor gene on chromosome 14q31 were associated with AITDs in t he Japanese population. A newly isolated growth factor, SEL1L, was recently mapped to 14q31, and we considered it an interesting candidate gene to exa mine with respect to both GD and MNG. We therefore have analyzed a dinucleo tide (CA)n repeat polymorphism in the intron 20 of the SEL1L gene in patien ts with AITDs and in normal subjects. The polymorphic marker was analyzed b y polymerase chain reaction (PCR) followed by electrophoresis on denaturing polyacrylamide gels. There was no significant difference in the distributi ons of SEL1L alleles between patients and controls. The present results do not support an association between a dinucleotide repeat polymorphism in in tron 20 of the SEL1L gene and AITD in Japanese women.