A strategy for PCR-amplification and sequencing of the flanking region
s in the polymorphism D2S44 (YNH24) has been developed based on the in
vestigations of Edwards et al. (1991). The flanking regions of the YNH
24 probe were successfully amplified and two distinct PCR products wit
h fragment sizes of 180 and 250 bp obtained. After asymmetric PCR and
didesoxy-sequencing 60 bp could be determined for every PCR fragment.
D2S44-specific primers were constructed which were located at the tran
sition between the flanking and repeat regions. Amplification conditio
ns were optimized using the YNH24 probe, different nuclease S1 concent
rations and incubation times. Optimized conditions were applied to the
amplification assay of human D2S44 alleles which had been investigate
d by RFLP analysis.