“…Most recently, the meta-analysis by Xia et al (95) reported that the TT genotype compared with the CC and CT genotypes carried a significantly greater risk of preeclampsia (by 76%) among Asian women only, whereas in Caucasian women this increased risk was not evident. It is worth noting however that a much greater number of large-scale studies in this area have been conducted within Asian populations with far fewer studies conducted in Caucasian populations; a factor that limits Sohda et al (87) 425 Japan 2·5 (1·3, 4·8) Grandone et al (88) 225 Italy 1·8 (1·0, 3·5) Kupferminc (96) 144 Israel 2·9 (1·0, 8·5) Powers et al (97) 237 Caucasian women 1·28 (0·58, 2·79) Kobashi et al (98) 316 Japan 0·68 (0·30, 1·55) Laivuori et al (99) 216 Finland 0·50 (0·14, 1·77) Rigo et al (100) 221 Caucasian women 1·13 (0·38, 3·37) Morrison et al (101) 404 Scotland 1·00 (0·55, 1·82) Prasmusinto et al (102) 112 Germany and Croatia 0·28 (0·03, 2·47) Pegoraro et al (103) 609 South African (Black) 0·62 (0·06, 6·90) Perez-Mutul et al (91) 325 Mexico 0·94 (0·59, 1·49) Williams et al (104) 304 Peru 1·6 (0·7, 3·8) Yilmaz et al (105) 111 Turkey 0·84 (0·26, 2·67) Also-Rallo et al (79) 165 Spain 0·73 (0·31, 1·76) Hernandez-Diaz et al (86) 154 USA/Canada 3·0 (1·2, 7·7) Stiefel et al (106) 584 Spain 0·92 (0·50, 1·71) the extent to which different populations can be compared. An additional limitation is that genotype-driven recruitment is generally not undertaken in these studies, a feature that is reflected by the relatively small numbers of pregnant women with the TT genotype being investigated and these raised the concern that many such studies may be statistically underpowered.…”