1 Introduction Hollak et al., 1994 Boot et al., 1998 CHIT1 Boot et al., 1998 Boot et al., 1998 Boot et al., 1998; Fusetti et al., 2002 Boot et al., 1998 Boot et al., 1998 Malaguarnera et al., 2003 Plasmodium falciparum Malaguarnera et al., 2003 Malaguarnera et al., 2003 Fuhrman and Piessens, 1985 Caenorhabditis elegans Zhang et al., 2005 Oesophagostomum dentatum Neuhaus et al., 1997 C. elegans chs-1 chs-2 chs-2 Zhang et al., 2005 CHIT1 Choi et al. (2001) Wuchereria bancrofti CHIT1 Hise et al., 2003 CHIT1 Brooker et al., 2004 Williams-Blangero et al., 1997 CHIT1 CHIT1 CHIT1 2 Materials and methods 2.1 Geographical location and study population Necator americanus Pritchard et al., 1990 Quinnell et al., 2004 2.2 Chitotriosidase genotyping by PCR Boot et al., 1998 2.3 Statistical analysis CHIT1 Wilson et al., 1996 Abecasis et al., 2000 F st Cockerham and Weir (1984) Goudet, 1995 F st F st http://research.marshfieldclinic.org/genetics/ Soranzo et al., 2005 3 Results χ 2 P CHIT1 CHIT1 Table 2 χ 2 p χ 2 p CHIT1 χ 2 p χ 2 p CHIT1 Table 1 F st F st CHIT1 F st F st F st F st F st F st P 4 Discussion N. americanus CHIT1 W. bancrofti Choi et al., 2001 Brugia malayi Fuhrman and Piessens, 1985; Schraermeyer et al., 1987 Acanthocheilonema vitae, N- Haslam et al., 1999 W. bancrofti Araujo et al., 1993 W. bancrofti Hise et al., 2003 C. elegans Zhang et al., 2005 N. americanus O. dentatum Neuhaus et al., 1997 Barone et al., 2003 CHIT1 Hise et al., 2003 Main et al., 2001 CHIT1 F st Akey et al., 2002 CHIT1 Malaguarnera et al. (2003) CHIT1 meso Choi et al., 2001; Chien et al., 2005 Barone et al. (2003) P. falciparum Di Luca et al., 2007 P. falciparum P. vivax CHIT1 Taken together, our data suggest that the chitotriosidase genotype does not play a major role in protection against hookworm infection, but this may be different in the case of lymphatic or cutaneous filariasis. However, there is no evidence for selection at this locus mediated by malaria or another tropical disease.