Population genetic analysis and conservation strategies for redtail shrimp Fenneropenaeus penicillatus using ten microsatellite markers.

Fenneropenaeus penicillatus, which is on the Red List of Endangered Species for China, is an important shrimp species. However, there is not enough genetic information on F. penicillatus for conservation and management purposes. Ten microsatellite markers were used to analyze the genetic diversity, genetic differentiation, and population structure of F. penicillatus to provide scientific information for the conservation of the species. Low genetic diversity and moderate genetic differentiation were found among 12 putative populations [Beihai, Dongshan (DS), Hainan (HN), Lianjiang, Nanao (NA), Ningde (ND), Putian, Quanzhou (QZ), Xiamen (XM), Shenzhen, Zhanjiang, and Zhangpu] along the southeast coast of China. QZ, XM, and DS exhibited the highest genetic diversity, while NA and ND had the lowest genetic diversity. Genetic differentiation among all populations, except HN, was low compared to the genetic differentiation between HN and the other 11 putative populations. These 12 putative populations were divided into two subgroups. One group consisted of XM, DS, and QZ. The other group consisted of the other eight putative populations with the exception of HN. The HN Island population requires further study due to its large genetic distance from the other 11 putative populations. Problems with the current conservation strategy are pointed out and suggestions given based on genetic information.

Genetic diversity and population structure of Fenneropenaeus penicillatus determined by mitochondrial DNA analyses.

Fenneropenaeus penicillatus is a widely distributed economically and ecologically important shrimp species, which is endangered in China. Sequence analysis of 16s rRNA and control region (CR) fragments from mitochondrial DNA was conducted to obtain information on genetic diversity and population structure. Individuals from 12 wild F. penicillatus populations located along the southeast coast of China were used. Polymerase chain reaction (PCR) fragments of the CR gene revealed high genetic diversity among the 12 populations; however, PCR fragments of the 16s rRNA gene revealed very low genetic diversity in the Hainan (HN) and Ningde (ND) populations and high genetic diversity in the DS, BH, PT, XM, and SZ populations. Data obtained from the CR and 16s rRNA genes suggested that high genetic differentiation exists among the 12 populations, which is mainly due to the high genetic differentiation between HN and all other 11 populations. These results may be useful for further sustainable management and utilization of this species.

Development and characterization of microsatellite loci in Megalonibea fusca.

Megalonibea fusca is a commercially important large edible fish. In this study, the first set of 10 polymorphic microsatellite loci for M. fusca was developed and characterized. The number of alleles per locus ranged from two to five, with the observed and expected heterozygosities ranging from 0.0667 to 0.7667, and from 0.0644 to 0.5828, respectively. Most of the loci were in Hardy-Weinberg equilibrium (P > 0.05), except for two loci (Mf25 and Mf30) after a Bonferroni's correction (P < 0.005). These informative microsatellite markers will be useful in further studies of the population and conservation genetics of this species.

Development of novel and polymorphic microsatellite DNA loci from Haliotis ovina.

Twelve microsatellite loci were developed from Haliotis ovina by the magnetic bead hybridization method. Genetic variability was assessed using 30 individuals from 3 wild populations. The number of alleles per locus ranged from 2 to 5, and the polymorphism information content ranged from 0.1228 to 0.6542. Observed and expected heterozygosities ranged from 0.0000 to 0.7778 and 0.1288 to 0.6310, respectively. These loci should provide useful information for genetic studies such as genetic diversity, pedigree analysis, construction of genetic linkage maps, and marker-assisted selection breeding in H. ovina.

Characterization of new microsatellite markers of Siganus fuscescens (Siganidae).

Siganus fuscescens, which is a small commercially important marine fish, is wildly distributed in shallow waters throughout the tropical and subtropical Indo-Pacific and Eastern Mediterranean regions. It is part of a group known as rabbitfish. Fifteen new polymorphic microsatellite markers for S. fuscescens were identified, and 32 wild individuals were used to evaluate the degree of polymorphism of these markers. The number of alleles per locus ranged from 2 to 12, and the polymorphism information content ranged from 0.210 to 0.849. The observed and expected heterozygosities were 0.142-0.808 and 0.225-0.853, respectively. Although significant deviations from Hardy-Weinberg equilibrium were detected at 2 loci (Sf1-37-2 and Sf1-47), no significant deviations were detected at the other 13 loci. These microsatellite markers will provide a useful tool for studies on genetic diversity and differentiation of S. fuscescens.

Characterization of eight novel microsatellite markers in the green-lipped mussel Perna viridis (Mytilidae).

The green lipped mussel, also known as the Asian green mussel (Perna viridis) is a fast reproducing and valuable food source, but it is also considered an invasive species and can clog and damage pipes and marine equipment. Eight novel polymorphic microsatellite loci for P. viridis were isolated and characterized. Microsatellite polymorphism was evaluated in 30 individuals collected from Xiamen, China. The number of alleles per locus and the polymorphism information content ranged from 2 to 5 and from 0.3092 to 0.7031, respectively. The observed and expected heterozygosities were 0.1538-0.8400 and 0.1448-0.6833, respectively. The loci identified in this study could provide a useful tool for the genetic population structure analysis of P. viridis.

Isolation and characterization of new microsatellite markers in the pen shell Atrina pectinata (Pinnidae).

The pen shell, Atrina pectinata, is a commercially important bivalve species, widely consumed in the Asian Pacific region. We identified 16 new microsatellite makers for A. pectinata using a modified fast isolation by AFLP of sequences containing repeat protocols; 27 individuals were collected from Xiamen to evaluate the degree of polymorphism. The number of polymorphic alleles per locus ranged from 2 to 11. The observed and expected heterozygosities were 0.050-0.913 and 0.049-0.869, respectively. The loci identified in this study could provide a useful tool for research on genetic diversity and genetic differentiation of A. pectinata populations.