ANALYSIS OF MICROSATELLITE MARKERS IN SICILIAN GOATS BREED FOR TRACEABILITY OF GIRGENTANA TYPICAL DAIRY PRODUCTS

Abstract

The establishment of useful analytical methods able to ensure the origin of the products, including the breed used, are important in maintaining the reliability of these products in order to develop a market segment. Traceability, obtained by molecular analysis, could be a reliable proposal for the authentication and valorization of animal products. In Sicily, the three most important dairy goat breeds are Girgentana (GR), Maltese (ML) and Derivata di Siria (DS). The GR is an endangered autochthonous goat breed. Preservation of endangered breeds could be achieved by establishing economic reasons for their survival. The aim of this work was to verify the use of microsatellite markers to assess a genetic traceability system to discriminate breeds and to detect adulteration in GR dairy products. A total of 314 individuals belonging to GR, ML, and DS goat breeds were genotyped at 24 microsatellite markers and a subset of 9 microsatellites was chosen for further analysis due to the presence of private alleles. The analyzed markers were FBC48, FBC20, CSRD247, SRCRSP5, OLADRB, SRCRSP8, OARAE54, SRCRSP24, and TGLA122. Fragments analysis of multiplex PCR was performed by capillary electrophoresis with ABI3130xl Genetic Analyzer. Allele frequency, average number of alleles, allelic richness (AR), Ho and He, PIC, and HWE for 9 loci were estimated using CERVUS 3.0.3 (Marshall et al., 1998), GENETIX (Belkhir et al., 1996), FSTAT 2.9.3.2 (Goudet, 1995) and POPGENE 1.31 (Yeh et al., 1999) software. The results showed high variability of markers subset considering that mean PIC values was 0.6449 and average number of alleles per locus was 8.67; AR ranged from 4.585 in TGLA122 to 8.980 in OLADRB. Six microsatellite markers from subset were not in HWE probably due to heterozygote excess (Ho=0.6133).In total 4 private alleles were found in GR, 8 in DS goat breeds and 2 in ML goat breed. The most frequent private alleles were 246 bp for CSRD247 in ML (0.32) and 177 bp for SRCRSP5 in DS (0.15), respectively. Private alleles of ML and DS goat breeds could be used for traceability of GR dairy products therefore further analysis will be performed in order to validate the possible use of these alleles on pool DNA samples extracted from mono‐breed dairy products.