Identification ability of tetraploid microsatellite loci in parentage analysis

An anadromous fish, the Chinese sturgeon (Acipenser sinensis Gray) is included in the 1996 IUCN Red List of Threatened Species. To save populations from extinction, artificial propagation had been sought since the 1980s and was achieved in 2009. Additional genetic information and methods will become crucial components in genetic management of the residual A. sinensis population. Microsatellite markers can provide information on the family structure, to avoid inbreeding or founder effects. However, the polyploidy derivative nature of the A. sinensis genome has added difficulties in settling these problems. Given the costs associated with genetic data collection, the trade-off between the amount of molecular data (how many loci are needed and which loci should be used) and the number of individuals sampled warrants consideration in order to maximize both efficiency and parentage analysis. Formulas to calculate the resolving power for tetraploid microsatellite loci in a given population are provided; these formulas are adapted from those fitted to the diploid loci in Neff et al. (Mol. Ecol., 9, 2000a, 515) and require genetic data only from the parent or parents in question, and an estimate of population allele frequencies. These formulas will help in addressing practical problems, such as the choice of genetic loci in A. sinensis conservation aquaculture programs.