Is there evidence of selection in the dopamine receptorD4 gene in Australian invasive starling populations?

• 来源期刊: 动物学报（英文版）
• 年，卷（期）: 2015,（3）
• 页码范围: 526-540
• 页数: 15页
• 语种: 英文

摘要

Although population genetic theory is largely based on the premise that loci under study are selectively neutral, it has been acknowledged that the study of DNA sequence data under the influence of selection can be useful. In some circumstances, these loci show increased population differentiation and gene diversity. Highly polymorphic loci may be especially useful when studying populations having low levels of diversity overall, such as is often the case with threatened or newly established inva-sive populations. Using common starlingsSturnus vulgaris sampled from invasive Australian populations, we investigated se-quence data of the dopamine receptor D4 gene (DRD4), a locus suspected to be under selection for novelty-seeking behaviour in a range of taxa including humans and passerine birds. We hypothesised that such behaviour may be advantageous when species encounter novel environments, such as during invasion. In addition to analyses to detect the presence of selection, we also esti-mated population differentiation and gene diversity usingDRD4 data and compared these estimates to those from microsatellite and mitochondrial DNA sequence data, using the same individuals. We found little evidence for selection onDRD4 in starlings. However, we did find elevated levels of within-population gene diversity when compared to microsatellites and mitochondrial DNA sequence, as well as a greater degree of population differentiation. We suggest that sequence data from putatively non- neutral loci are a useful addition to studies of invasive populations, where low genetic variability is expected [Current Zoology 61 (3): 505–519, 2015].