Identification of polygyne and monogyne fire ant colonies (Solenopsis invicta) by multiplex PCR of Gp-9 alleles

Oligonucleotide primers were designed to discriminate between the Gp-9(B) and Gp-9(b) alleles found in monogyne and polygyne colonies of fire ant, Solenopsis invicta Buren. Primers specific for the Gp-9(B) allele produced a 517 bp amplicon and primers, specific for Gp-9(b) allele produced a 423 bp amplicon. When both sets of primers were multiplexed, homozygous monogyne ants produced a single 517 bp amplicon (specific for Gp-9(B)), whereas heterozygous polygyne ants produced one 517 bp amplicon and one 423 bp amplicon (specific for Gp-9(B) and Gp-9(b), respectively) which allowed the Gp-9 alleles to be discerned in a single reaction. This method was tested on ants from 20 monogyne colonies and 20 polygyne colonies and was 100% accurate in discriminating the two forms.