[An unusual paternity dispute case: classical methods did not rule out either of the two possible fathers].

The author described an uncommon case when neither of two men (former husband and another man) who were considered possible fathers of the child, could be ruled out as potential fathers based on examination of signs of 19 erythrocyte, serum and enzyme systems and 59 HLA-A, B, C antigens and their subtypes. The eliminating capacity of the examination was 99.86%; paternity was, based on probability calculation, practically proved (p = 99.9925% and 99.90%). According to statements of parties in the dispute the other man is the child's father. The author discusses perspectives of DNA examinations.