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runs were carried out at 4 V/cm for 20min on 2% agarose gels, made using 0.5 x TBE
buffer with ethidium bromide (10 mg/ml) for staining ofDNA fragments. PCR products
were purified using ExoSAP-IT (USB Corporation), and sequenced using an extemal
sequencing core service (Macrogen Inc., Korea). Each mitochondrial region was
sequenced in both forward and reverse directions and the corresponding sequencing
runs were repeated twice in order to verify the reliability of results.

Data analysis: Sequences were aligned using the program Clustal W (Thompson
et al. 1994), implemented in BioEdit 7.0.5.2 software package (Hall 1999), and
deposited in GenBank (Accession Nos.XXXX).

The best probabil istic model of sequence evolution was determined for each
mtDNA region using the program jModeltest 0.1.1 (Posada 2008) with a maximum
likelihood optimised search, using the Akaike Information Criterion (AIC).

Within population genetic vari ability -was estimated taking into accout
insertion/deletions; number of polymorphic sites (S), number of haplotypes (H),
nucleotide diversity (n), haplotype diversity (h), and mean number of pa1rw1se
differences (d), were estimated with the software package DnaSP 5.10 (Librado and
Rozas 1999).

Genetic relationships among individuals were checked by a Median-Joining
network (Bandelt et al. 1999), using the software package Network 4.5.0.1
(www.fluxus-engineering.com). Transitions and transversions were equally weighted,
whereas, for the COI region, mutations were inversely weighted according to the
estimated number of mutational changes (more weight was given to mutational events
that occurred only once).

The occurrence of genetic structuring among samples was investigated by the
Bayesian model-based clustering algorithm implemented in Baps 5.2 (Corander and

54

Gìan Luca Dedola: ANALISI DELLA VARIABILITÀ GENETICA DI PATELLA FéRRUGINEA, PATEL-LA ULl'SSIPONENSIS (MOLLUSCA: GASTROPODA) E PINNA
NOBILIS (MOLLUSCA: BIVALVIA): lLCONTRJBUTO DEl DATI MOLECOLARI ALLA CONSERVAZIONE DI SPECIE MINACCIATE- Tesi di douorato in Scienze
della natura e delle sue risorse • indiri7.zo BK>logi.a Ambientale, Università degli Studi di Sassarl