Prenatal HLA typing of uncultured amniocytes prior to the collection of related allogeneic cord blood

DNA samples isolated from corresponding uncultured amniotic fluid, cord blo od and maternal blood (n=5) were subjected to low resolution typing of the HLA-A, -B and -DRB loci by the polymerase chain reaction using sequence-spe cific primers (PCR-SSP). Furthermore, the effect of ethylene diamine tetraa cetate disodium salt (EDTA) on the quality of genomic DNA isolated from amn iotic fluid samples after long-term storage was evaluated. Unambiguous resu lts of HLA typing could be achieved from all amniotic fluid samples stabili zed with EDTA. KR-SSP typing failed in DNA samples from amniotic fluid with out the addition of EDTA. In all cases the fetal HLA type could be confirme d by the result from the corresponding cord blood typing. Contamination wit h maternal DNA led to additional weak PCR-SSP bands in one case, but data i nterpretation was still unambiguous. Reliable fetal BLA typing can be achie ved directly from amniotic fluid and culturing of amniocytes is not require d.