Polymorphisms in the IL-13 gene associated with asthma are described at Arg130Gln (rs20541) (also described as Arg164Gln, Gln110Arg, +2044 NIaIV RFLP, and Arg144Gln based on IPI, Unit-ProtKB/Swiss-Prot, EMBL CDS databases) in a coding region of the IL-13 gene [19,97,105]. Here, IL13 is linked to asthma.