RAPD MARKERS OF POTENTIAL USE IN PENAEID PRAWN (PENAEUS-MONODON) BREEDING PROGRAMS

Single, short generic primers of arbitrary sequence used to amplify DN A from Penaeus monodon gave three polymorphic markers out of the total of 48 bands that amplified. This level of polymorphism is similar to that displayed by other taxa (6-7%) and suggests randomly amplified po lymorphic DNA (RAPD) approaches will be as useful in providing markers for prawn breeding programs as they have been for other species. Fift y offspring from each of the six families screened for the three polym orphic markers demonstrated that all the markers conformed to Mendelia n expectations for band presence/absence, consistent with a model of c omplete or co-dominance where dominant homozygotes and heterozygotes d isplay a band but homozygote recessives do not. A fourth primer amplif ied a band in almost all of the progeny but in none of the adults, and was probably derived from algal or bacterial epicommensals contaminat ing the sample, emphasising the need to establish the inheritance of R APD polymorphisms prior to their use as genetic markers.