Analysis of Lingo1 variant in sporadic and familial essential tremor among Asians

OBJECTIVE - Genome-wide association study (GWAS) has identified a variant in LINGO1 (rs9652490) that increases the risk of essential tremor (ET) among Caucasians. It has been suggested that among Asians, the risk variant is relevant only for the familial forms of ET. We investigated the association of the rs9652490 variant with sporadic and familial ET in a Chinese population and conducted a pooled analysis to compare the potential differential effect between sporadic and familial ET. METHODS - rs9652490 was genotyped by direct sequencing in 117 ET and 160 controls in a Chinese population. Previous published data from another Asian population were included in the meta-analysis. RESULT - There were no significant differences in the minor allele frequency and genotype frequency between ET and controls in our Chinese population. However, in the pooled analysis involving 1201 subjects, patients with ET had a higher proportion of GG genotype compared to controls. Logistic regression analysis revealed that G allele increased the risk of ET via a recessive model. In both familial ET and sporadic ET, the G allele increased the risk via a recessive model. CONCLUSION -  While we could not demonstrate a significant association of the rs9652490 variant in our own study, pooled analysis of a much larger cohort revealed for the first time that the variant increased the risk in both familial and sporadic forms of ET among Asians, though the effect was stronger in familial ET.