A MINICHROMOSOME CARRYING A PIGMENTATION GENE AND BROOK TROUT DNA-SEQUENCES IN TRANSGENIC RAINBOW-TROUT

We describe the transmission of an introduced minichromosome of brook trout (Salvelinus fontinalis) origin, carrying a pigmentation gene, th rough three generations in rainbow trout (Oncorhynchus mykiss). The mi nichromosome was originally introduced into gynogenetic albino rainbow trout using gamma-irradiated brook trout sperm. In the third generati on, the presence of the minichromosome was correlated with pigmentatio n. A brook trout specific interspersed repeat DNA sequence, Fok I, was also correlated with pigmentation in these individuals. This system, the first clearly documented example of induced chromosome mediated ge ne transfer at the organismal level, could have applications in studie s of gene mapping, development, gene regulation, and chromosome functi on.