A novel point mutation within the EDA gene causes an exon dropping in mature RNA in Holstein Friesian cattle breed affected by X-linked anhidrotic ectodermal dysplasia

<p>Abstract</p> <p>Background</p> <p>X-linked anhidrotic ectodermal dysplasia is a disorder characterized by abnormal development of tissues and organs of ectodermal origin caused by mutations in the <it>EDA </it>gene. The bovine <it>EDA </it>gene encodes the ectodysplasin A, a membrane protein expressed in keratinocytes, hair follicles and sweat glands, which is involved in the interactions between cell and cell and/or cell and matrix. Four mutations causing ectodermal dysplasia in cattle have been described so far.</p> <p>Results</p> <p>We identified a new single nucleotide polymorphism (SNP) at the 9^thbase of exon 8 in the <it>EDA </it>gene in two calves of Holstein Friesian cattle breed affected by ectodermal dysplasia. This SNP is located in the exonic splicing enhancer (ESEs) recognized by SRp40 protein. As a consequence, the spliceosome machinery is no longer able to recognize the sequence as exonic and causes exon skipping. The mutation determines the deletion of the entire exon (131 bp) in the RNA processing, causing a severe alteration of the protein structure and thus the disease.</p> <p>Conclusion</p> <p>We identified a mutation, never described before, that changes the regulation of alternative splicing in the <it>EDA </it>gene and causes ectodermal dysplasia in cattle. The analysis of the SNP allows the identification of carriers that can transmit the disease to the offspring. This mutation can thus be exploited for a rational and efficient selection of unequivocally healthy cows for breeding.</p

Genetic variation and relationships among Turkish water buffalo populations

The genetic variation and relationships among six Turkish water buffalo populations,typical of different regions was assessed using a set of twenty-six heterologous (bovine) microsatellite markers. Between 7 and 17 different alleles were identified per microsatellite in a total of 254 alleles. The average number of alleles across all loci in all the analyzed populations was found to be 12.57. The expected mean heterozygosity (HE) per population was between 0.5 and 0.58. Significant departures from Hardy-Weinberg equilibrium were observed for 44 locus-population combinations. Population differentiation was analyzed by estimation of the FST index (values ranging from 0.053 to 0.123) among populations. In the PCA analysis the Merzifon population showed the highest differentiation compared to the others. Also some individuals of the Danamandira population appeared clearly separated. Instead Afyon, Coskun, Pazar and Thural populations represented one single cluster. The assignment of individuals to their source populations, performed using the Bayesian clustering approach implemented in STRUCTURE 2.2 software, has evidenced a high differentiation of Merzifon and Danamandira populations as well. The results of this study could be useful for the development of conservation strategies of the Turkish buffalo

Comparison of Milk Fat Globule Membrane (MFGM) Proteins of Chianina and Holstein Cattle Breed Milk Samples Through Proteomics Methods

Identification of proteins involved in milk production is important to understand the biology of lactation. Many studies have advanced the understanding of mammary function and milk secretion, but the critical molecular mechanisms implicated in milk fat secretion is still incomplete. Milk Fat Globules are secreted from the apical surface of the mammary cells, surrounded by a thin membrane bilayer, the Milk Fat Globule Membrane (MFGM), formed by proteins which have been suggested to be holesterolemia-lowering factors, inhibitors of cancer cell growth, vitamin binders, bactericidal, suppressors of multiple sclerosis. Using a proteomic approach, we compared MFGM from milk samples of individuals belonging to two different cattle breeds, Chianina and Holstein,representative of selection for milk and meat traits, respectively. We were able to isolate some of the major MFGM proteins in the examined samples and to identify differences between the protein fractions of the two breeds. We detected differences in the amount of proteins linked to mammary gland development and lipid droplets formation, as well as host defence mechanisms. We have shown that proteomics is a suitable, unbiased method for the study of milk fractions proteins and a powerful tool in nutritional genomics