Genotyping of microsatellite markers to study genetic structure of the wild striped snakehead Channa striata in Malaysia

Abstract

Genetic variability and differences in wild striped snakehead Channa striata from Malaysia were analysed by genotyping nine novel nuclear microsatellite loci. Analysis revealed moderate-to-high genetic diversity in most of the populations, indicative of large effective population sizes. The highly diversified populations are admixed populations and, therefore, can be recommended as potential candidates for selective breeding and conservation since they each contain most of the alleles found in their particular region. Three homogenous groups of the wild populations were identified, apparently separated by effective barriers, in accordance with contemporary drainage patterns. The highest population pairwise FST found between members of the same group reflects the ancient population connectivity; yet prolonged geographical isolation resulted in adaptation of alleles to local contemporary environmental change. A significant relationship between genetic distance and geographical isolation was observed (r = 0·644, P < 0·01). Anthropogenic perturbations indicated apparent genetic proximity between distant populations.

Population genetic structure of Asian snakehead fish (Channa striata) in North Borneo: Implications for conservation of local freshwater biodiversity

“…Per population estimates of genetic diversity of C. striata in this study (Table 3; overall A R = 4.23, range of A R : 3.00-5.20; overallĤ E = 0.53, range ofĤ E : 0.43-0.67) were within the spectra of diversity estimates reported for populations in the Mekong River Basin (Adamson et al, 2012; overall A R = 4.04, range of A R : 2.04-4.94, overall H E = 0.67, range ofĤ E : 0.34-0.77) and throughout Malaysia (Tan et al, 2016: overall A R = 4.76, range of A R : 3.00-7.63, overallĤ E = 0.58, range ofĤ E : 0.3-0.76). Tan et al (2016) study also quantified intra-population diversity of C. striata in Papar (A R = 4.29,Ĥ E = 0.55) and Kota Belud (A R = 3.00,Ĥ E = 0.36), which were roughly similar with our measurements (Papar: A R = 4.75,Ĥ E = 0.50; Kota Belud: A R = 3.77,Ĥ E = 0.43). We attribute slight discrepancies in these estimates to differences in the number of markers and sample sizes, which are more parsimonious than citing temporal variations as sampling periods in both independent assessments were overlapping: between 2007 and 2010 in Tan et al (2016) and between 2010 and 2013 in this study.…”

“…With respect to current knowledge on the phylogeographical structuring of C. striata, the connectivity of the palaeodrainage in the Sunda plains may well be extended from west Borneo (Sarawak, Malaysia) to its northwest (west coast of Sabah). The earlier proposition that C. striata populations throughout the Malaysian Borneo are homogeneous (Tan et al, 2012(Tan et al, , 2016 is refuted herein as more comprehensive sampling revealed that the east Sabah populations constitute a distinct clade altogether. Concurrently, our findings echo the claim by Inger and Chin (1962) such that a "large part" of North Borneo (i.e., the northeastern region) was isolated (or became disconnected due to saline intrusion much earlier) from the palaeo-river system that previously connected a large expanse of freshwater ecosystems in the Sunda shelf.…”

“…Tan et al (2016) study also quantified intra-population diversity of C. striata in Papar (A R = 4.29,Ĥ E = 0.55) and Kota Belud (A R = 3.00,Ĥ E = 0.36), which were roughly similar with our measurements (Papar: A R = 4.75,Ĥ E = 0.50; Kota Belud: A R = 3.77,Ĥ E = 0.43). We attribute slight discrepancies in these estimates to differences in the number of markers and sample sizes, which are more parsimonious than citing temporal variations as sampling periods in both independent assessments were overlapping: between 2007 and 2010 in Tan et al (2016) and between 2010 and 2013 in this study. Overall, we can conclude that the C. striata populations in Sabah possess comparatively moderate genetic diversity.…”

“…Meanwhile, mountain ranges constitute effective physical barriers to genetic exchange among deeply divergent clades of C. striata in Peninsula Malaysia (Jamsari, Tan, & Siti-Azizah, 2011a;Tan, Jamsari, Muchlisin, & Siti-Azizah, 2015;Tan, Jamsari, & Siti-Azizah, 2012). The magnitude of genetic differentiation between populations of the species has been suggested to systematically be a function of spatial and temporal isolations among them (Siti-Balkhis, Jamsari, Tan, Yasin, & Siti-Azizah, 2011;Tan, Jamsari, & Siti-Azizah, 2016). Moreover, natural inclination of C. striata to persist in a particular habitat on a geological timescale makes it a suitable model from which the evolutionary history of the drainage system in an area can be extrapolated (Adamson et al, 2012;Adamson, Hurwood, & Mather, 2010).…”

Research Article Isolation and characterization of polymorphic microsatellite markers for the chub mackerel (Scomber japonicus) and cross-species amplification in the blue mackerel (S. australasicus).

“…Moreover, they have been widely developed and used in the study of population genetics of many species (Guo et al, 2016;Mohanty et al, 2016;Tan et al, 2016). Furthermore, some of these microsatellite markers developed for Scomber species have been successfully used for amplification in other related species (Tang et al, 2009;Divya et al, 2016).…”