Thus, the variation in genotype distribution between RA cases and controls, and the associations between RA and risk allele of the AFF1 rs340630 polymorphism under dominant and recessive models were evaluated by logistic regression, with the adjustment of age and gender.
Thus, the variance in genotype distribution between RA cases and controls, and the associations of RA with the risk allele of the AFF1 rs340630 polymorphism under the dominant and recessive model were evaluated by logistic regression with the adjustment of gender.
In the present study, we have adopted the strategy of replicating the association of RA with genetic polymorphism within AFF1, which was previously found to be associated with SLE in a GWAS and in multi-staged replication studies integrating the expression of quantitative trait loci in a Japanese population (11).
The AFF gene family consists of AFF1 [also known as ALL1-fused gene from chromosome 4 (AF4)], AFF2 [also known as fragile X mental retardation 2 (FMR2)], AFF3 [also known as lymphoid nuclear protein related to AF4 (LAF4)], and AFF4 [also known as ALL1-fused gene from 5q31 (AF5q31) or major CDK9 elongation factor associated-protein (MCEF)] (21).
In a GWAS and in multi-staged replication studies carried out in a Japanese population, a new genetic association between AFF1 rs340630 polymorphism and genetic predisposition to SLE with genome-wide significance level was identified (11).
Notably, replication studies conducted in Chinese (18) and Iranian (27) populations did not find significant evidence for the association of AFF1 rs340630 polymorphism with SLE.
In conclusion, our study represents the first report examining the association of AFF1 rs340630 polymorphism with genetic susceptibility to RA in a Chinese population, and no significant evidence was found.
A genome-wide association study identified AFF1 as a susceptibility locus for systemic lupus eyrthematosus in Japanese.
Association of AFF1 rs340630 and AFF3 rs10865035 polymorphisms with systemic lupus erythematosus in a Chinese population.
Association Study of an AFF1 gene polymorphism (rs340630) with Iranian systemic lupus erythematosus patients.