Abstract
Finding optimal sample sizes is critical for the accurate estimation of genetic diversity of large invasive populations. Based on previous studies, we hypothesized that a minimal sample size of 3–8 individuals is sufficient to dissect the population architecture of the harlequin lady beetle, Harmonia axyridis, a biological control agent and an invasive alien species. Here, equipped with a type IIB endonuclease restriction site-associated (2b-RAD) DNA sequencing approach, we identified 13,766 and 13,929 single nucleotide polymorphisms (SNPs), respectively, among native and invasive H. axyridis populations. With this information we simulated populations using a randomly selected 3000 SNPs and a subset of individuals. From this simulation we finally determined that six individuals is the minimum sample size required for the accurate estimation of intra- and inter-population genetic diversity within and across H. axyridis populations. Our findings provide an empirical advantage for population genomic studies of H. axyridis in particular and suggest useful tactics for similar studies on multicellular organisms in general.
Highlights
Using optimal sample sizes to accurately estimate genetic diversity of large natural populations is an imperative issue in the analysis of evolutionary processes [1]
We conducted a rigorous empirical determination of the optimal sample size in an invasive ladybeetle, H. axyridis, which confirmed our hypothesis that a minimal sample size of 3–8 individuals is sufficient to estimate genetic diversity within and across native and invasive populations
Only one published study has examined a reliable number of individuals to address invasive population genomics using single nucleotide polymorphisms (SNPs) markers [23], while several studies have investigated the impact of sample size based on microsatellite markers [5,8,38,39,40,41]
Summary
Using optimal sample sizes to accurately estimate genetic diversity of large natural populations is an imperative issue in the analysis of evolutionary processes [1]. Because larger samples per population than needed for accurate estimation, results in extra expense and wastes much time to analysis [2], while limited sample sizes will lead to significant errors in estimating the genetic diversity of species [3,4,5]. Using microsatellites markers to analyze population genetics of invasive species could be a concern, since a recent study showed that low genetic diversity or genuine multimodality was observed [11]. Given these disadvantages of microsatellites marker in genetic analysis, a growing number of researches have recommended to use the genomic data over microsatellites for genetic study [12,13,14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
