Linkage in cattle between the major histocompatibility complex (BoLA) and the M blood group system

Relationships between the bovine Major Histocompatibility Complex (MHC) and 11 blood group systems were examined using genetic information obtained from 58 families with doubly-heterozygous parents. The data were analyzed by the lod-score method: Close to moderate linkage between the cattle MHC (BoLA complex) and 10 blood group loci, A, B, C, F, J, L, S, Z, R’ and T’ was excluded. Evidence for a close linkage between BoLA and the M blood group system is presented and a recombination frequency of 0.04 was estimated. The possibility of a linkage disequilibrium in the BoLA-M system chromosomal region is suggested.Les relations entre le Complexe Majeur d’Histocompatibilité (CMH) des bovins et les 11 systèmes de groupes sanguins ont été examinées en utilisant l’information génétique recueillie dans 58 familles de parents double-hétérozygotes. Les données ont été analysées par la méthode du lod-score. Toute liaison génétique étroite ou modérée entre le CMH bovin (complexe BOLA) et 10 des loci de groupes sanguins : A, B, C, F, J, L, S, Z, R’ et T’ est exclue. L’existence d’une liaison génétique étroite entre BoLA et le système M de groupes sanguins est établie, avec une fréquence de recombinaison estimée à 0,04. La possibilité d’un déséquilibre de liaison au sein de la région chromosomique BoLA-système M est suggérée

Traceability of the PGI product "Vitellone Bianco dell'Appennino Centrale" by SNP markers

AbstractTraceability of meat has become a key aspect of food-quality assurance and a priority for EU countries, to meet consumer demand for comprehensive and integrated food safety policies. In this context, the traceability of animals and animal products at the breed level might play a key role as it would enable the certification of regional products linked to particular breeds. Technologies based on DNA analysis have the potential to achieve this goal bypassing the large scale and systematic biological sampling necessary for individual fingerprinting.The objective of this work was to test the power of a SNP panel to trace PGI "Vitellone Bianco dell'Appennino Centrale", a product linked to three breeds: Chianina, Marchigiana and Romagnola.A total of 180 unrelated animals belonging to PGI-allowed breeds (Chianina n=22; Romagnola n=22; and Marchigiana n=22) and PGI-not allowed breeds (Piemontese n=22, Maremmana n=24, Italian Red Pied n=24, Italian Brown n=22, Italian Friesian n=22) were sampled and genoty..

Haplotype association analysis of meat quality traits at the bovine PRKAG3 locus

The current study presents the results of a preliminary haplotype association analysis at the bovine PRKAG3 locus with meat quality traits in the Chianina breed. No significant association was shown between haploid haplotypes (or diplotypes) and phenotypical traits after applying a Bonferroni correction for multiple comparison. Nonetheless, data from Longissimus dorsi muscle suggest the presence of a statistically non-significant trend toward an influence of the PRKAG3 haploid haplotypes on meat colour (a*) and water holding capacity (M/T) traits, as confirmed also by diplotype-based association analysis. A less clear set of results was observed for the Triceps brachii and Semitendinosus muscles

Cosmid-derived markers anchoring the bovine genetic map to the physical map

The mapping strategy for the bovine genome described in this paper uses large insert clones as a tool for physical mapping and as a source of highly polymorphic microsatellites for genetic typing, and was one objective of the BovMap Project funded by the European Union (UE). Eight-three cosmid and phage clones were characterized and used to physically anchor the linkage groups defining all the bovine autosomes and the X Chromosome (Chr). By combining physical and genetic mapping, clones described in this paper have led to the identification of the linkage groups corresponding to Chr 9, 12, 16, and 25. In addition, anchored loci from this study were used to orient the linkage groups corresponding to Chr 3, 7, 8, 9, 13, 16, 18, 19, and 28 as identified in previously published maps. Comparison of the estimated size of the physical and linkage maps suggests that the genetic length of the bovine genome may be around 4000 c

rs5888 Variant of SCARB1 Gene Is a Possible Susceptibility Factor for Age-Related Macular Degeneration

Major genetic factors for age-related macular degeneration (AMD) have recently been identified as susceptibility risk factors, including variants in the CFH gene and the ARMS2 LOC387715/HTRA1locus. Our purpose was to perform a case-control study in two populations among individuals who did not carry risk variants for CFHY402H and LOC387715 A69S (ARMS2), called “study” individuals, in order to identify new genetic risk factors. Based on a candidate gene approach, we analyzed SNP rs5888 of the SCARB1 gene, coding for SRBI, which is involved in the lipid and lutein pathways. This study was conducted in a French series of 1241 AMD patients and 297 controls, and in a North American series of 1257 patients with advanced AMD and 1732 controls. Among these individuals, we identified 61 French patients, 77 French controls, 85 North American patients and 338 North American controls who did not carry the CFH nor ARMS2 polymorphisms. An association between AMD and the SCARB1 gene was seen among the study subjects. The genotypic distribution of the rs5888 polymorphism was significantly different between cases and controls in the French population (p<0.006). Heterozygosity at the rs5888 SNP increased risk of AMD compared to the CC genotypes in the French study population (odds ratio (OR) = 3.5, CI95%: 1.4–8.9, p<0.01) and after pooling the 2 populations (OR = 2.9, 95% CI: 1.6–5.3, p<0.002). Subgroup analysis in exudative forms of AMD revealed a pooled OR of 3.6 for individuals heterozygous for rs5888 (95% CI: 1.7–7.6, p<0.0015). These results suggest the possible contribution of SCARB1, a new genetic factor in AMD, and implicate a role for cholesterol and antioxidant micronutrient (lutein and vitamin E) metabolism in AMD

The significance of the complement system for the pathogenesis of age-related macular degeneration — current evidence and translation into clinical application

BACKGROUND: Dysregulation of the complement system has been shown to play a major role in the pathogenesis of age-related macular degeneration (AMD). METHODS: The current evidence from human studies derives from immunohistochemical and proteomic studies in donor eyes, genetic association studies, and studies of blood complement protein levels. These lines of evidence are corroborated by in vitro and animal studies. RESULTS: In AMD donor eyes, detection of complement proteins in drusen suggested local inflammatory processes involving the complement system. Moreover, higher levels of complement proteins in the Bruch's membrane/choroid complex could be detected in AMD donor eyes compared to controls. A large number of independent genetic studies have consistently confirmed the association of AMD with risk or protective variants in genes coding for complement proteins, including complement factor H (CFH), CFH-related proteins 1 and 3, factor B/C2, C3 and factor I. Another set of independent studies detected increased levels of complement activation products in plasma of AMD patients, suggesting that AMD may be a systemic disease and the macula a vulnerable anatomic site of minimal resistance to complement activation. Genotype-phenotype correlations, including the impact of genetic variants on disease progression, gene-environment and pharmacogenetic interactions, have been investigated. There is evidence that complement gene variants may be associated with the progression from early to late forms of AMD, whereas they do not appear to play a significant role when late atrophic AMD has already developed. There are indications for an interaction between genetic variants and supplementation and dietary factors. Also, there is some evidence that variants in the CFH gene influence treatment effects in patients with neovascular AMD. CONCLUSIONS: Such data suggest that the complement system may have a significant role for developing new prophylactic and therapeutic interventions in AMD. In fact, several compounds acting on the complement pathway are currently in clinical trials. Therapeutics that modulate the complement system need to balance inhibition with preservation of sufficient functional activity in order to maintain adequate immune responses and tissue homeostasis. Specifically, targeting the dysfunction appears more adequate than a global suppression of complement activation in chronic diseases such as AMD