Association of the DJ-1 gene polymorphism with sporadic Parkinson's disease in Sichuan province of China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the frequencies of three polymorphisms in DJ-1 (g.168-185del; SNP405, refSNP ID:rs3766606 and 293 G/A) and their association with sporadic Parkinson's disease.</p><p><b>METHODS</b>An association study was performed to determine the genotype of each subject using polymerase chain reaction, restriction fragment length polymorphism and sequence analysis in 192 patients with sporadic Parkinson's disease and 198 healthy controls.</p><p><b>RESULTS</b>In the g.168-185del locus, the Ins/Ins genotype was common and the frequency of Del allele was very low (0.38%). The SNP of 293G/A was not detected in both groups. In the SNP405 G/T site, the GT genotype frequency was significantly higher in patients with age of onset before 40 years than in controls (18.75% vs 5.54%, P=0.004, OR=6.30 95%CI:1.96-20.18).</p><p><b>CONCLUSION</b>The results suggest that the frequencies of the g.168-185del and 293G/A polymorphisms might be different between Chinese and European. The SNP405 GT genotype might be a risk factor for sporadic Parkinson's disease with early age of onset in Sichuan Han population.</p>

Association of the polymorphisms in NURR1 gene with Parkinson's disease / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the association between the polymorphisms of [c.-2922(C)2-3 and IVS6+ 18insG] in the NURR1 gene and Parkinson's disease (PD) in a Han population from Sichuan province.</p><p><b>METHODS</b>PCR, allele-specific PCR (AS-PCR) and restriction fragment length polymorphism (RFLP) were used to determine the genotype of each subject.</p><p><b>RESULTS</b>The two polymorphic sites in 241 PD patients and 236 controls with matched age, gender and ethnicity were analyzed. In the IVS6+ 18insG site, the difference of genotype frequencies of 3G/3G, 3G/2G and 2G/2G was not statistically significant. However, the 3G/2G genotype frequency was significantly higher in the PD with age of onset being < 50 years than that in controls (chi (2)= 6.537, P= 0.011; OR= 1.913, 95%CI: 1.159-3.158). No significant differences were found in allele and genotype frequencies of the c.-2922(C)2-3 site in the promoter region between the PD and controls (P= 0.766).</p><p><b>CONCLUSION</b>This study suggested that the IVS6+ 18insG polymorphism may be associated with genetic susceptibility of PD with age of onset being < 50 years and the c.-2922(C)2-3 site in the promoter region may not be a risk factor for PD in authors' patient group.</p>

Transmission disequilibrium test of DRD4 exon III 48bp variant number tandem repeat polymorphism and tic disorder / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate whether DRD4 exon III48 bp variant number tandem repeat(VNTR) polymorphism is associated with tic disorder.</p><p><b>METHODS</b>One hundred and twenty-two nucleus families were collected using Structured clinical interview for genetic study of Tourette syndrome and related disorders for family-based association analysis of tic disorder and DRD4 exon III 48bp VNTR polymorphism. One hundred and twenty-two trios were divided into two groups: tic disorder group (82 trios of Tourette syndrome or chronic tic disorder, TS&CT) and tic disorder accompanied with attention deficit and hyperactivity disorder (ADHD) group (40 trios of Tourette syndrome or chronic tic disorder accompanied with ADHD, TS&ADHD). Transmission disequilibrium test (TDT), in addition to polymerase chain reaction and VNTR technique were conducted in 122 trios.</p><p><b>RESULTS</b>There exist 5 alleles at this polymorphic locus in this sample including DRD4 exon III 48bp 2-6 repeats. No transmission disequilibrium was found between DRD4 exon III 48 bp VNTR and tic disorder (chi square=7.44, P 0.12); however, when the sample was divided into two groups, transmission disequilibrium was noticed between the cases of TS&ADHD and this locus by overall allele-wise analysis (chi square=11.74, P 0.02), and there exists transmission disequilibrium exclusively between 5 or 6 repeats of 48bp VNTR(longer alleles) by allele-wise analysis (chi square=10.57, P 0.032, chi square=6.13, P 0.01). No transmission disequilibrium was seen between TS&CT and DRD4 exon III 48bp VNTR(chi square=3.38, P 0.50).</p><p><b>CONCLUSION</b>The results of this study have revealed an association between the longer alleles of DRD4 exon III 48bp VNTR polymorphism and tic disorder accompanied with ADHD, thus suggesting a possible genetic risk factor of tic disorder accompanied with ADHD in Chinese.</p>