APOLIPROTEIN-B POLYMORPHISM - APPLICATION TO MONITORING EARLY BONE-MARROW TRANSPLANTATION IN SAUDI POPULATION

Seventy-three unrelated Saudi individuals and seven consecutive bone m arrow transplant donor-recipient pairs were studied to characterize an d determine the frequency of 3' apolipoprotein B alleles by polymerase chain reaction. The samples analyzed were either peripheral blood or bone marrow aspirates. Eleven different alleles were detected. The ind ex of heterozygosity was 0.66. Apolipoprotein B analysis was informati ve in 57% of the studied donor-recipient pairs. Engraftment was detect ed as early as day three post-transplantation. The threshold of detect ion of this allele was up to 0.01 x 10(6)/ml. Mixed chimerism of the o rder of 1% could be detected. We concluded that apolipoprotein B is a highly polymorphic allele among the Saudi population and this makes th e region a useful marker for monitoring engraftment following allogene ic bone marrow transplantation.