Molecular Ecology Notes (2002) 2, 453 – 455 doi: 10.1046/j.1471-8278 .2002.00275.x © 2002 Blackwell Science Ltd Blackwell Science, Ltd PRIMER NOTE Highly variable microsatellite loci for studies of introduced populations of the small Indian mongoose (Herpestes javanicus ) C.-G. THULIN,* N. GYLLENSTRAND,† G. MCCRACKEN* and D. SIMBERLOFF* *Department of Ecology and Evolutionary Biology, University of Tennessee, 569 Dabney Hall, Knoxville, Tennessee 37996, USA, †Department of Conservation Biology and Genetics, EBC, Uppsala University, Norbyvägen 18D, 752 36 Uppsala, Sweden Abstract During their introduction, non-native species typically undergo founder events that reduce gen- etic variation. To allow a high-resolution genetic investigation of introduced populations of the small Indian mongoose (Herpestes javanicus), we developed primers for nine variable microsatellite loci. Their applicability was assessed in 10 mongooses from the large Fijian population, which originated from a single pair from Calcutta, India. The number of alleles ranged from two to five per locus, possibly as a result of preservation of initial variability and in situ mutations during the rapid population expansion after introduction. Keywords: Herpestes javanicus, Herpestidae, microsatellite, mongoose, primers Received 20 March 2002; revision received 29 May 2002; accepted 18 June 2002 Within recently introduced populations, the combina- tion of random drift and small initial propagule sizes may cause loss of genotypes and thereby induce genotypic (and subsequently phenotypic) differentiation from ance- stral populations (Falconer & Mackay 1996). Similarly, the founder event and subsequent drift are expected to result in lowered genetic variation within introduced populations. Thus, highly variable markers are needed for investiga- tion of the genetic variation and differentiation within and between introduced populations of the small Indian mon- goose (Herpestes javanicus, formerly H. auropunctatus). This is particularly important in this species, because the docu- mented founder propagule is usually limited, exemplified on the Fiji Islands where a single pair brought from Calcutta, India, in 1883, founded the current population of thousands (M. Gorman, personal communication). Length polymorphisms in autosomal microsatellite motifs can be useful for studies of species with low levels of genetic variation (Hughes & Queller 1993). To find markers with a high degree of polymorphism for genetic investigations of H. javanicus, we constructed a microsatel- lite library and optimized polymerase chain raction (PCR) conditions for a subset of nine highly variable loci following the protocol of Fleischer & Loew (1995; also M. Hamilton & R. Fleischer, personal communication) with some modifications. Whole genomic DNA from one H. javanicus male from Pakistan was kindly provided by Ulfur Arnason (University of Lund, Sweden). A total of 5.4 μg was digested with Sau3AI (Promega) and the resulting fragments in a range of 100 –1000 base pairs were excised with the Chromaspin Fragment Separation Kit (ClonTech). The fragments were ligated to pre-annealed double-stranded linkers (SaulA 5′-GCG GTA CCC GGG AAG CTT GG-3′ annealed to SaulB 5′-GAT CCC AAG CTT CCC GGG TAC CGC-3′, providing a CTAG overhang) to enable PCR multiplication of template fragments, which was performed before and after micro- satellite enrichment. For enrichment, the template fragments were hybridized with a total of 12 3′-biotinylated di-, tri- and tetra-repeat oligonucleotides; (AC) 10 (AG) 10 (ACC) 7 (AGG) 7 (ATT) 7 (GAA) 9 (GAC) 7 (GAT) 9 (GCA) 7 (GTA) 9 (GTT) 9 (AAAG) 7 . Successfully hybridized fragments were captured on streptavidin beads, Dynabeads M-280 (DYNAL), eluted at an oligospecific temperature and then amplified with an additional PCR cycle, using SaulA as primer. Linkers were then removed by digestion with MboI. The microsatellite- enriched template was purified with a QiaQuick PCR Purification Kit (Qiagen) and then ligated into BamHI digested vector PBS Bluescript SK + (Stratagene). Super- competent Escherichia coli bacteria Epicurian Coli® XL1-Blue (Stratagene) were transformed with the ligated vector using Correspondence: Carl-Gustaf Thulin. Fax: + 1865 9743067; E-mail: carl-gustaf.thulin@ebc.uu.se