Table 2.
Association between depression and genetic or environmental factors.
| Case | Control | χ2 | df | P | |
|---|---|---|---|---|---|
| Genotypes | 6.36 | 2 | 0.04 | ||
| G/G | 384 (65) | 386 (66) | |||
| G/A | 177 (30) | 188 (32) | |||
| A/A | 29 (5) | 13 (2) | |||
| Homozygous | 5.47 | 1 | 0.01 | ||
| G/* | 561 (95) | 574 (98) | |||
| A/A | 29 (5) | 13 (2) | |||
| Alleles | 1.08 | 1 | 0.29 | ||
| G | 945 (80) | 960 (82) | |||
| A | 235 (20) | 214 (18) | |||
| Threatening life events | 64.27 | 2 | 1.105e−14* | ||
| No | 229 (39) | 363 (62) | |||
| 1 | 167 (28) | 117 (20) | |||
| 2 or more | 194 (33) | 107 (18) | |||
| Family history | 66.55 | 1 | 3.408e−16* | ||
| Negative | 499 (85) | 576 (98) | |||
| Positive | 91 (15) | 11 (2) |
*P <0.01 after Bonferroni correction.