Individual and population variation in invertebrates revealed by Inter-simple Sequence Repeats (ISSRs)

Abstract

PCR-based molecular markers are well suited for questions requiring large scale surveys of plant and animal populations. Inter-simple Sequence Repeats or ISSRs are analyzed by a recently developed technique based on the amplification of the regions between inverse-oriented microsatellite loci with oligonucleotides anchored in microsatellites themselves. ISSRs have shown much promise for the study of the population biology of plants, but have not yet been explored for similar studies of animals. The value of ISSRs is demonstrated for the study of animal species with low levels of within-population variation. Sets of primers are identified which reveal variation in two aphid species, Acyrthosiphon pisum and Pemphigus obesinymphae, in the yellow fever mosquito Aedes aegypti, and in a rotifer in the genus Philodina.

Figure 1.

ISSR banding patterns for multiple genotypes in each of three species. Size standards in base pairs are in the left most lanes. A: Nine adult aphids (Pemphigus obesinymphae) collected from different clones at a single locality, amplified by the 3′-anchored primer (AC)⁸G (UBC no. 827). Arrows highlight several of the unambiguously variable bands.; B: ISSR banding patterns ((AC)⁸G) for two individual P. obesinymphae aphids each from two different clones. Clone-specific bands are indicated by arrows.