We observed statistically significant differences in genotypic and allelic frequencies of rs1721100 between PD cases and controls but not for rs12720208.
The meta-analysis showed an association between FGF20 gene rs1721100 polymorphism and risk of Parkinson's disease under a recessive model (GG versus CG+GG; OR = 1.15, 95 % CI 1.02-1.29, p = 0.02) but not under a dominant model (CG+GG versus CC; OR = 1.03, 95 % CI 0.93-1.13, p = 0.57).
Results in this study revealed that the rs1721100(C/G) polymorphism is a risk factor for PD in Han Chinese population, while rs12720208(C/T) polymorphism is not significantly associated with PD.
In order to clarify the association between the FGF20 gene and Parkinson's disease, we attempted to replicate this association by a case-control association study using a large number of Japanese samples (1388 patients and 1891 controls). rs1721100 exhibited a significant difference in allele C versus G (P=0.0089), and in genotype CC+CG versus GG (P=0.0053).
We discovered a highly significant association of PD with one intronic SNP, rs1989754 (P=.0006), and two SNPs, rs1721100 (P=.02) and ss20399075 (P=.0008), located in the 3' regulatory region in our overall sample.