FREQUENT DETECTION OF BCL-2 J(H) TRANSLOCATIONS IN HUMAN BLOOD AND ORGAN SAMPLES BY A QUANTITATIVE POLYMERASE CHAIN-REACTION ASSAY/

Using an ultrasensitive assay involving the PCR, we have examined the frequency of a follicular lymphoma-associated translocation in periphe ral blood from 132 individuals, most of whom were healthy blood donors . This translocation occurs between the bcl-2 proto-oncogene and the J (H) gene region and prolongs the life of lymphocytes. At a level of se nsitivity of 1 translocation-bearing cell per 5 x 10(6) cells, almost one-half of healthy human adults had this translocation in the mononuc lear fraction of peripheral blood. However, the range of frequency of these translocations spanned almost three orders of magnitude among tr anslocation-positive individuals. Furthermore, there was a statistical ly significant increase with age in the percentage of individuals who were translocation positive. Such an age correlation was also seen for the percentage of blood donors with rather high translocation frequen cies (greater than or equal to 20 per 5 x 10(6) peripheral blood monon uclear cells). However, the blood donor who had by far the highest con centration of this translocation was a healthy 35-year-old male contai ning similar to 900 apparently monoclonal, translocation-bearing cells per 5 x 10(6) peripheral blood mononuclear cells. Our findings sugges t that some individuals who may be at risk for follicular lymphoma mig ht be able to be identified by this PCR assay an peripheral blood. Als o, these data may help explain the age dependence of the occurrence of this cancer.