Novel genetic variants of the Platelet Activating Factor Receptor (PTAFR) gene are described. Various genotypes, haplotypes, and haplotype pairs that exist in the general United States population are disclosed for the PTAFR gene. Compositions and methods for haplotyping and/or genotyping the PTAFR gene in an individual are also disclosed. Polynucleotides defined by the haplotypes disclosed herein are also described.
