The Hardy-Weinberg Equilibrium (HWE) tests were performed in the control group (non-IPA patients) by a standard observedexpected chi-square (x 2 ) test at each polymorphic site (http://ihg2. helmholtz-muenchen.de/cgi-bin/hw/hwa1.pl). Unconditional logistic regression was used to assess the main effects of the genetic polymorphisms on IPA risk using co-dominant, dominant and recessive inheritance models. For each SNP, the more common allele in the control group was assigned as the reference category. All analyses were adjusted for age, gender, hematological malignancy and established risk factors for IPA infection (HSCT, neutropenia, GVHD and corticoid therapy use) and were conducted using the statistical software SSPS (version 14.0, SPSS Inc., Chicago, USA). All tests were considered to be statistically significant with a p value of ,0.05. Adjustment for multiple testing was carried out following a conservative threshold for statistical significance, based on a revised version of the Bonferroni method: we calculated for each gene the ''number of effective independent variables'' (M eff ) by use of the SNP Spectral Decomposition approach (http://gump.qimr. edu.au/general/daleN/SNPSpDsuperlite/) [38] . We obtained a study-wise M eff value by adding up the gene M eff 's. SNPtool (http://www.dkfz.de/de/molgen_epidemiology/tools/ SNPtool.html) [39] and the Haploview v4.2 software were used for LD blocks reconstruction and haplotype association statistics. Block structures were determined according to the method of Gabriel et al. [40] .