The objective of this study was to investigate eight INDEL polymorphisms in seven genes involved in modulation of the host immune response, including CYP19A1 [rs11575899], NFKβ1 [rs28362491], IL1α [rs3783553], CASP8 [rs3834129], UGT1A1 [rs8175347], PAR1 [rs11267092], and CYP2E1 [INDEL 96pb], besides one VNTR (variable number tandem repeat) of 70 bp on intron 3 of IL4 [rs79071878] in a group consisting of 141 leprosy patients and 180 healthy individuals, to identify possible susceptibility markers of leprosy and evaluate the influence of genetic ancestry on disease risk. Here, IL4 is linked to leprosy.