OPA-LIKE REPEATS IN THE GENOME OF THE MEDFLY CERATITIS-CAPITATA

The sequence determination of several genomic clones isolated from the Mediterranean fruitfly Ceratitis capitata identified the existence of opa-like repeats, often more than one being clustered in small chromo somal segments. These repeats have previously been shown to consist of stretches of tandemly reiterated glutamine-encoding residues, and the y are found in multiple genes of several organisms. Most of the repeat s described here are flanked or interrupted by stop codons in all read ing frames and, thus, could not possibly be part of protein-coding seq uences. Furthermore, these repeats, of which there are several hundred in the genome of the Medfly, can be used effectively for the determin ation of sequence polymorphisms, providing a convenient approach to ob tain additional landmarks for the construction of genomic maps of this economically important insect.