Table 1. Discovery and replication sample characteristics.
| Sample | Country | N | % Users | % Female | Mean age (range) | N SNPs |
|---|---|---|---|---|---|---|
| Discovery | ||||||
| ALSPAC | UK | 2976 | 42 | 56 | 18 (17–19) | 5 182 231 |
| BLTS | Australia | 721 | 60 | 57 | 26 (18–33) | 4 558 509 |
| CADD | USA | 853 | 79 | 30 | 25 (18–36) | 4 972 726 |
| EGCUT1 | Estonia | 2765 | 1.3 | 55 | 34 (18–66) | 6 048 479 |
| EGCUT2 | Estonia | 970 | 4.8 | 51 | 31 (18–50) | 5 171 164 |
| FinnTwin | Finland | 1029 | 27 | 52 | 23 (20–29) | 4 364 135 |
| HUVH | Spain | 981 | 20 | 30 | 36 (17–87) | 4 971 170 |
| MCTFR | USA | 6241 | 59 | 54 | 37 (18–71) | 6 304 767 |
| NTR | Netherlands | 4653 | 27 | 66 | 37 (18–60) | 4 644 238 |
| QIMR | Australia | 6778 | 51 | 54 | 45 (18–85) | 5 901 727 |
| TRAILS | Netherlands | 1226 | 51 | 47 | 19 (18–21) | 5 336 901 |
| Utrecht | Netherlands | 1173 | 54 | 54 | 21 (18–37) | 4 831 885 |
| Yale Penn EA | USA | 1964 | 92 | 40 | 38 (16–76) | 5 856 902 |
| Replication | ||||||
| Radar | Dutch | 338 | 59 | 44 | 20 (17–22) | 10 |
| SYS | Canada | 551 | 51 | 56 | 50 (36–65) | 10 |
| TwinsUK | UK | 2078 | 12 | 93 | 58 (18–86) | 10 |
| Yale Penn AA | US | 2660 | 82 | 46 | 42 (16–76) | 10 |
Abbreviations: N, sample size; N SNPs, number of SNPs used for the meta-analysis; SNP, single-nucleotide polymorphism; % female, percentage of females; % users, percentage of users that ever used cannabis.