Table 5.
Distribution of the DRD4 polymorphisms and assignment to groups
| Genotype | n | % | 
|---|---|---|
| DRD4-no7 (n = 262) | ||
| 2/2 | 4 | 1.0 | 
| 2/3 | 3 | 0.7 | 
| 2/4 | 34 | 8.4 | 
| 2/5 | 1 | 0.2 | 
| 2/6 | 1 | 0.2 | 
| 3/4 | 28 | 6.9 | 
| 3/5 | 1 | 0.2 | 
| 4/4 | 173 | 42.7 | 
| 4/5 | 7 | 1.7 | 
| 4/6 | 4 | 1.0 | 
| 4/8 | 5 | 1.2 | 
| 5/5 | 1 | 0.2 | 
| DRD4-7r (n = 143) | ||
| 2/7 | 9 | 2.2 | 
| 3/7 | 7 | 1.7 | 
| 4/7 | 111 | 27.4 | 
| 5/7 | 1 | 0.2 | 
| 7/7 | 14 | 3.5 | 
| 7/8 | 1 | 0.2 | 
DRD4-no7 includes participants with no 7-repeat alleles. DRD4-7r includes participants with at least one 7-repeat allele. The three most common repeat frequencies in our sample were the 4-repeat (66 %), the 7-repeat (19 %), and the 2-repeat (7 %)