Peptidylarginine deiminases (PADIs) are post-translational modification enzymes that catalyze the conversion of protein-bound arginine residues into citrulline residues in the presence of calcium ions. Among PADIs, PADI4 was identified as a rheumatoid arthritis-susceptibility gene (Suzuki et al. in Nat Genet 34:395, 2003). We identified a total of 87 single nucleotide polymorphisms (SNPs) in PADI1 and PADI3 gene loci. Following a comparison of our data with SNPs in the dbSNP database in the National Center for Biotechnology Information, 45 SNPs are considered to be novel: 33 were identified in the PADI1 gene locus and 12 in the PADI3 gene locus. We also identified two insertion-deletion polymorphisms in introns of the PADI1. The high-resolution map that we constructed in this study will serve as a useful resource for analyzing gene scans of complex diseases mapped to this local segment on chromosomal band 1p36.13.