http://www.benecke.com/developm.html
Due to the low amount of cells (epithelia) in urine, analysis of hypervariability in short tandem repeated sequences of genomic DNA (STRs) by use of PCR seems to be the only way of individualization [2,4,9]. To identify urine samples in cases of uncertain donorship like doping in sports or routine doping/ID controls, respectively, we co-amplified three short and sensitive non-overlapping STR loci. To take into consideration that storage may lead to degradation of DNA [9], short allelic ranges of &st;300 bp were chosen.
http://www.bxscience.edu/publications/forensicbio/articles/toxicology/h-toxi02.htm
Doctors from Johns Hopkins University and the Fox Chase Cancer Center in Philadelphia were able to detect a cancer- associated DNA change in the urine of men who had early stage prostate cancer. The researchers reported that the DNA urine test could also offer a useful tool for detecting early stage disease.