Table 3.
Genotype and allele frequencies for PsA patients and controls before and after stratification for race (Indians and Caucasians)
| Frequency, n (%) | Controls | PsA patients | p value | RR (95% CI) | OR (95% CI) |
|---|---|---|---|---|---|
| Unstratified: Indians + Caucasians (PsA patients: n = 116 and controls: n = 100) | |||||
| Genotype, n (%) | |||||
| GG | 52 (52) | 43 (37.07) | 0.0595a1 | ||
| GC | 44 (44) | 63 (54.31) | |||
| CC | 4 (4) | 10 (8.62) | |||
| GC + CC | 48 (48) | 73 (62.93) | 0.0290b | 1.38 (1.04–1.84) | 1.84 (1.07–3.17) |
| Allele, n (%) | |||||
| G | 148 (74) | 149 (64.22) | 0.0295c | 1.29 (1.02–1.65) | 1.59 (1.05–2.40) |
| C | 52 (26) | 83 (35.78) | |||
| Stratified: Indians (PsA patients: n = 84 and controls: n = 62) | |||||
| Genotype, n (%) | |||||
| GG | 37 (59.68) | 31 (36.90) | 0.0241a2 | ||
| GC | 22 (35.48) | 46 (54.76) | |||
| CC | 3 (4.84) | 7 (8.33) | |||
| GC + CC | 25 (40.32) | 53 (63.10) | 0.0075b | 1.70 (1.15–2.51) | 2.53 (1.29–4.96) |
| Allele, n (%) | |||||
| G | 96 (77.41) | 108 (64.29) | 0.0200c | 1.48 (1.05–2.08) | 1.91 (1.13–3.22) |
| C | 28 (22.58) | 60 (35.71) | |||
| Stratified: Caucasians (PsA patients: n = 32 and controls: n = 38) | |||||
| Genotype, n (%) | |||||
| GG | 15 (39.47) | 12 (37.50) | 0.4793a3 | ||
| GC | 22 (57.89) | 17 (53.13) | |||
| CC | 1 (2.63) | 3 (9.38) | |||
| GC + CC | 23 (60.52) | 20 (62.5) | 0.9383b | 1.04 (0.67–1.61) | 1.09 (0.41–2.86) |
| Allele, n (%) | |||||
| G | 52 (68.42) | 41 (64.06) | 0.5955c | 1.10 (0.78–1.53) | 1.22 (0.60–2.46) |
| C | 24 (31.58) | 23 (35.04) | |||
CI confidence interval, DF degrees of freedom, RR relative risk, OR odds ratio, PsA psoriatic arthritis, χ2 Chi-squared test
a1, a2, a3Chi squared p value (controls genotypes vs. PsA patients genotypes) (a1 χ2 = 5.644, 2 DF; a2 χ2 = 7.454, 2 DF; a3 χ2 = 1.471, 2 DF). bFisher’s exact test p value (GG vs. GC + CC genotypes). cFisher’s exact test p value (controls G and C alleles vs. PsA patients G and C alleles). A p < 0.05 was considered as being significant