Inheritance of Fifteen Microsatellite Loci in Ceratitis capitata (Diptera: Tephritidae)

Abstract

Molecular methods that rely on microsatellite markers have been developed for population genetic studies and diagnostics of tephritid pest species such as the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Whereas many of these markers are tested to see if they are within the Hardy-Weinberg equilibrium, very few markers developed for pest species are tested to ensure the selected alleles behave according to the laws of Mendelian inheritance. Fifteen previously developed microsatellite markers were examined for Mendelian inheritance. Nine parental groups consisting of a laboratory reared parent and a wild type parent and their respective progeny were examined. In total, 174 flies, consisting of 90 males and 84 females, were analyzed. Seventy-seven segregation ratio tests were performed to determine if any departures from expected Mendelian inheritance occurred. Representatives from each of the observed alleles were cloned and sequenced. Troubleshooting was performed on loci that did not conform to expected Mendelian inheritance ratios to confirm the cause and improve laboratory procedures. Issues observed included incomplete adenylation at the 5′ end in Ccmic3, the presence of artifactual bands leading to false calls in Ccmic25, and monomorphic alleles in Ccmic7. Only 1 locus, Ccmic25, deviated from Mendelian expectations after protocol optimization in the form of a detected transmission ratio distortion leading to excessive heterozygosity. Finally, 1 locus, Ccmic9, showed evidence of allelic homoplasy.