Sequencing analyses of genomic DNA samples from a Chinese population identified four single-nucleotide polymorphisms (SNPs) of the CRTH2 gene, encoding a chemoattractant receptor predominantly expressed on Th2 cells and a receptor for prostaglandin D2 (PGD2). Two coding-region SNPs with a T to G and a C to A substitutions, resulting in codon changes from Phe to Val and Pro to Thr, respectively. Two additional SNPs were discovered in the 3' untranslated region (3'-UTR). These newly identified SNPs will be useful for further functional study of variant CRTH2 gene, and for genetic studies of asthma and other immunologic diseases.