Ina Sternstein

A new single nucleotide polymorphism in the rabbit (Oryctolagus cuniculus) myostatin (MSTN) gene is associated with carcass composition traits

This study aimed at the identification of genetic variations in the myostatin (MSTN) gene and testing their effects on carcass quality traits. We comparatively sequenced Giant Grey (GG) and New Zealand White (NZW) rabbits that were founders of a cross-bred population. Alignment of our sequence data with the GenBank sequence of the rabbit MSTN gene (Ensembl Gene ID ENSOCUG00000012663) identified three single nucleotide polymorphisms (SNPs). The two novel SNPs (c.-125T>C, c.373+234G>A) and one known SNP (c.747+34C>T) were subsequently analysed for linkage with carcass composition traits in 363 F2 animals of the cross GG × NZW. Significant linkage was found between c.373+234G>A and nine carcass composition traits (P < 0.05). No significant effects were found for c.-125T>C and c.747+34C>T. Because the linked SNP is located in intron 1 and no genetic variation was found in the coding region, further investigations are necessary to understand the functional effect of the c.373+234G>A variant on the variability of the traits.

A comprehensive linkage map and QTL map for carcass traits in a cross between Giant Grey and New Zealand White rabbits

BackgroundGenomic resources for the rabbit are still limited compared to many other livestock species. The genomic sequence as well as linkage maps have gaps that hamper their use in rabbit genome research. Therefore, the aims of this study were the improvement of existing linkage maps and the mapping of quantitative trait loci (QTL) for carcass and meat quality traits. The study was performed in a F2 population of an initial cross between Giant Grey (GG) and New Zealand White (NZW) rabbits. The population consisted of 363 F2 animals derived from 9 F1 bucks and 33 F1 does. 186 microsatellite and three SNP markers were informative for mapping.ResultsOut of 189 markers, which could be assigned to linkage groups, 110 markers were genetically mapped for the first time. The average marker distance was 7.8 cM. The map across all autosomes reached a total length of 1419 cM. The maternal linkage map was 1.4 times longer than the paternal. All linkage groups could be anchored to chromosomes. On the basis of the generated genetic map, we identified a highly significant QTL (genome-wide significance p < 0.01) for different carcass weights on chromosome 7 with a peak position at 91 cM (157 Mb), a significant QTL (p < 0.05) for bone mass on chromosome 9 at 61 cM (65 Mb), and another one for drip loss on chromosome 12 at 94 cM (128 Mb). Additional suggestive QTL were found on almost all chromosomes. Several genomic loci affecting the fore, intermediate and hind parts of the carcass were identified. The identified QTL explain between 2.5 to 14.6% of the phenotypic variance in the F2 population.ConclusionsThe results present the most comprehensive genetic map and the first genome-wide QTL mapping study for carcass and meat quality traits in rabbits. The identified QTL, in particular the major QTL on chromosome 7, provide starting points for fine mapping and candidate gene search. The data contribute to linking physical and genetic information in the rabbit genome.