Table 1.
Descriptives for cognitive phenotypes and COMT genotypes/diplotypes by sex.
| Phenotype data | Boys |
Girls |
p | ||
|---|---|---|---|---|---|
| n total | Mean (SD) | n total | Mean (SD) | ||
| Cognition at age 8 | |||||
| Word reading | 1024 | −0.07 (1.04) | 1046 | 0.07 (0.96) | 0.002 |
| Vocabulary | 1024 | 0.04 (1.00) | 1046 | −0.04 (1.00) | 0.06 |
| Reading comprehension | 1024 | −0.07 (1.03) | 1046 | 0.07 (0.96) | 0.001 |
| Picture intelligence | 1029 | 0.01 (1.01) | 1046 | −0.01 (1.00) | 0.75 |
| Cognition at age 15 | |||||
| AH4 Verbal Ability | 1027 | 0.02 (1.01) | 1047 | −0.02 (0.98) | 0.26 |
| Reading Comprehension | 1029 | −0.06 (1.02) | 1047 | 0.06 (0.97) | 0.007 |
| Mathematics | 1028 | 0.18 (1.06) | 1047 | −0.17 (0.91) | <0.0001 |
| AH4 Non-verbal Ability | 1028 | 0.09 (1.00) | 1048 | −0.09 (1.00) | <0.0001 |
| Genotype data | n | Freq (%) | n | Freq (%) | p |
|---|---|---|---|---|---|
| COMT genotypes | |||||
| rs737865: CC/CT/TT | 995 | 9.8/38.3/51.9 | 1031 | 8.7/41.2/50.1 | 0.36 |
| rs6269: GG/AG/AA | 1016 | 17.6/48.2/34.2 | 1038 | 17.0/46.9/36.1 | 0.64 |
| rs4818: GG/CG/CC | 1020 | 17.8/47.8/34.4 | 1037 | 16.6/47.2/36.2 | 0.62 |
| rs4680: GG/AG/AA | 1020 | 24.5/50.8/24.7 | 1034 | 23.1/50.4/26.5 | 0.58 |
| rs165599: GG/AG/AA | 1008 | 9.8/40.7/49.5 | 1028 | 9.2/41.3/49.4 | 0.89 |
| COMT diplotypes* | |||||
| ValA/ValA | 181 | 17.8 | 175 | 16.9 | |
| ValA/Met | 428 | 42 | 426 | 41.1 | |
| ValA/ValB or Met/Met | 315 | 31 | 334 | 32.3 | |
| ValB/Met | 86 | 8.5 | 93 | 9 | |
| ValB/ValB | 7 | 0.7 | 7 | 0.7 | 0.94 |
Note: COMT diplotype = rs6269–rs4818–rs4680; reference groups are CC–for rs737865, GG–for 165599, ValA/ValA–for Nackley's diplotype.