MICROSATELLITE INSTABILITY IN HUMAN TESTICULAR GERM-CELL TUMORS

DNA samples obtained from 29 testicular germ cell, tumours have been s creened for instability at nine different microsatellite sequences con sisting of dinucleotide, trinucleotide and tetranucleotide loci. Overa ll, in tumours from six (21%) patients we found abnormalities in at le ast one of the loci examined. Mutation was most frequently found in te tranucleotide and trinucleotide repeats with only a low proportion of alterations in dinucleotide repeats. This pattern of instability is di stinct from that reported in colorectal cancer and other cancers that have a high level of alterations in dinucleotide repeats.