The FBI has published its thirteen core loci for the Combined DNA Index System (CODIS) database. STR Fact Sheets are available for all thirteen loci (click on locus name for the STR Fact Sheet).
For more information, see:
Butler, J.M. (2006) Genetics and
genomics of core STR loci used in human identity testing.
J. Forensic Sci.
51(2): 253-265.
Genotype Profiles for six Population Groups at the 13 CODIS Short Tandem Repeat Core Loci and Other PCR-Based Loci (Click on "Link to raw data" at the bottom of the page).
U.S. population data collected by NIST - allele frequencies for 13 CODIS STR loci + D2S1338 and D19S433