ISOLATION AND CHARACTERIZATION OF MICROSATELLITE MARKERS IN THE BLACKTIGER PRAWN PENAEUS-MONODON

Isolation and characterization of microsatellite sequences from the ge nome of the black tiger prawn Penaeus monodon are described. Ninety-se ven (GT)(n) and 16 (CT)(n) microsatellites were isolated from partial genomic libraries composed of 18,000 and 5250 clones, respectively. Th e genomic library screening indicated that (GT)(n) microsatellites are more abundant than (CT)(n) in P. monodon genome. The microsatellite s equences were classified into three categories, perfect, imperfect, an d compound. The predominant categories found in P. monodon microsatell ites are imperfect repeats for both (GT)(n) and (CT)(n). Very long rep eat arrays were found in P. monodon microsatellite clones, which resul ted in difficulties in primer design. Two microsatellite loci, CUPmo 1 8 and CUPmo 386, were successfully amplified. The number of alleles of each locus was preliminarily determined. For the CUPmo18 locus, Mende lian inheritance was tested by analysis of genotypic ratios in F-1 off spring and their parents. The results of this study demonstrate the pr esence of highly polymorphic microsatellite markers in P. monodon. The se markers will be useful in population studies and parental determina tion in P. monodon. However, the low abundance and difficulties in obt aining a large number of usable microsatellite loci indicated that the se markers may not be appropriate for use in genome mapping of this sp ecies.