“…One study contained four case-control studies from different ethnicities (Gilliland et al, 2002), and two studies contained two individual case-control studies, respectively (Kamada et al, 2007;Minelli et al, 2010). Finally, 19 casecontrol studies from 14 publications with 4,543 childhood asthma cases and 19,394 controls were included into this meta-analysis (Vavilin et al, 2000;Gilliland et al, 2002;Kabesch et al, 2004;Lee et al, 2005;Ercan et al, 2006;Hanene et al, 2007;Kamada et al, 2007;Li et al, 2009;Henderson et al, 2010;Lima et al, 2010;Minelli et al, 2010;Tung et al, 2011;Karam et al, 2012;Piacentini et al, 2012). Among those 19 case-control studies, 8 (75.0%) were from Caucasian populations, and 6 (12.5%) were from Asians and 3 from Africans (Table 1).…”