Research Article

Association of CHRNA4 gene rs1044396 and rs1044397 polymorphisms with Parkinson’s disease symptoms and smoking

Published: May 12, 2015
Genet. Mol. Res. 14 (2) : 5112-5122 DOI: 10.4238/2015.May.12.14

Abstract

We assessed the CHRNA4 exon 5 rs1044396 and rs1044397 polymorphisms and investigated their relationship with Parkinson’s disease (PD) severity and several non-motor symptoms. Ninety-seven patients with primary PD and 108 controls were recruited, and their smoking history identified. Patients with PD were assessed using the unified PD rating scale (UPDRS), Hoehn & Yahr (H&Y) grade, Hamilton depression rating scale (HAMD), visual analogue 10-points scale (VAS), and the Pittsburgh sleep quality index (PSQI). Polymerase chain reaction amplification and direct sequencing was performed on genomic DNA to identify polymorphic variants. Statistical analysis demonstrated that there were no gender differences in rs1044396(C→T) and rs1044397(G→A) frequencies. More smokers were identified among carriers of rs1044396 CT/TT genotypes. We also found no differences between PD and control groups in frequencies of either polymorphism. However, in women, PD onset was latest in rs1044397 GA/AA (P = 0.015). rs1044396 CT/TT genotype carriers and rs1044397 GG genotype patients with PD had higher VAS scores. No differences were found on the course of PD, H&Y grade, or UPDRS-II or -III scores between various genotypes, nor were differences found on scores of HAMD, nocturia, or PSQI in PD patients. Our results suggested that the CHRNA4 rs1044396 CT/TT genotype is related to cigarette smoking, that the rs1044397 polymorphism may associate with PD age of onset in women, and that rs1044396 and rs1044397 may relate to pain in PD patients, but not to the course or severity of disease, or to depression or nocturnal or sleeping disorders.

We assessed the CHRNA4 exon 5 rs1044396 and rs1044397 polymorphisms and investigated their relationship with Parkinson’s disease (PD) severity and several non-motor symptoms. Ninety-seven patients with primary PD and 108 controls were recruited, and their smoking history identified. Patients with PD were assessed using the unified PD rating scale (UPDRS), Hoehn & Yahr (H&Y) grade, Hamilton depression rating scale (HAMD), visual analogue 10-points scale (VAS), and the Pittsburgh sleep quality index (PSQI). Polymerase chain reaction amplification and direct sequencing was performed on genomic DNA to identify polymorphic variants. Statistical analysis demonstrated that there were no gender differences in rs1044396(C→T) and rs1044397(G→A) frequencies. More smokers were identified among carriers of rs1044396 CT/TT genotypes. We also found no differences between PD and control groups in frequencies of either polymorphism. However, in women, PD onset was latest in rs1044397 GA/AA (P = 0.015). rs1044396 CT/TT genotype carriers and rs1044397 GG genotype patients with PD had higher VAS scores. No differences were found on the course of PD, H&Y grade, or UPDRS-II or -III scores between various genotypes, nor were differences found on scores of HAMD, nocturia, or PSQI in PD patients. Our results suggested that the CHRNA4 rs1044396 CT/TT genotype is related to cigarette smoking, that the rs1044397 polymorphism may associate with PD age of onset in women, and that rs1044396 and rs1044397 may relate to pain in PD patients, but not to the course or severity of disease, or to depression or nocturnal or sleeping disorders.

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