The frequency distributions of the length of restriction fragments (HinfI) revealed by RFLP-analysis (restriction fragment length polymorphism) of blood samples from 482 Danish Caucasians using the single locus VNTR (variable number of tandem repeats) probes MS1, MS31, MS43a and YNH24 are reported. From two blood samples three fragments were obtained with MS1. The consistency of the characteristic allele frequency distribution for each probe is exemplified by comparing the accumulated frequency curves obtained with MS43a in samples consisting of 50 and 920 bands, respectively. The distribution of the differences in migration distance for the two fragments of a bandpair was investigated. The results suggest that the high frequency of apparent homozygotes observed is due mainly to coalescence of close heterozygotes. The distribution of frequencies of 437 DNA-profiles is reported.