Deletion in the EVC2 gene causes chondrodysplastic dwarfism in Tyrolean grey cattle

During the summer of 2013 seven Italian Tyrolean Grey calves were born with abnormally short limbs. Detailed clinical and pathological examination revealed similarities to chondrodysplastic dwarfism. Pedigree analysis showed a common founder, assuming autosomal monogenic recessive transmission of the defective allele. A positional cloning approach combining genome wide association and homozygosity mapping identified a single 1.6 Mb genomic region on BTA 6 that was associated with the disease. Whole genome re-sequencing of an affected calf revealed a single candidate causal mutation in the Ellis van Creveld syndrome 2 (EVC2) gene. This gene is known to be associated with chondrodysplastic dwarfism in Japanese Brown cattle, and dwarfism, abnormal nails and teeth, and dysostosis in humans with Ellis-van Creveld syndrome. Sanger sequencing confirmed the presence of a 2 bp deletion in exon 19 (c.2993_2994ACdel) that led to a premature stop codon in the coding sequence of bovine EVC2, and was concordant with the recessive pattern of inheritance in affected and carrier animals. This loss of function mutation confirms the important role of EVC2 in bone development. Genetic testing can now be used to eliminate this form of chondrodysplastic dwarfism from Tyrolean Grey cattle

Identification of the causative mutation of congenital pseudo-myotonia in Chianina cattle

Abstract: Congenital pseudo-myotonia (PMT) in Chianina cattle is a muscle function disorder which is mainly characterized by an exercise-induced muscle contracture which prevents animals from performing muscular activities more intense than a simple walk at a slow pace. Mutations in the human ATP2A1 gene, encoding a fast-twitch skeletal-muscle Ca2+ ATPase (SERCA1), cause Brody myopathy, a very similar rare autosomal recessive disorder characterized by exercise-induced muscle cramps and impaired muscle relaxation. The analysis of the collected Chianina pedigree data suggested monogenic autosomal recessive inheritance and revealed that all PMT affected individuals traced back to a single founder sire. A family with 16 PMT affected cattle was genotyped with two bovine ATP2A1 gene flanking microsatellites.Linkage analysis within this family showed that the PMT mutation could be assigned to the ATP2A1 gene region on BTA25 (LOD score >3). Subsequent DNA sequencing of the 16 PMT affected calves revealed a missense mutation (c.491G>A) leading to a p.Arg164His substitution in exon 6 of ATP2A1. Arg164 in bovine ATP2A1 is located within the functional important N-terminal actuator domain and is a highly conserved residue. Genotyping 112 unaffected unrelated Chianina animals did not reveal a single individual homozygous for mutation and indicated a carrier frequency of >0.10

Inherited diseases of cattle

This review focus on the most important inherited disorders of cattle and the genomic basis is presented when known. In addition it deals with aspects that should be considered when dealing with this type of diseases and finally, a survey of different alterations in the bovine genome is presented. The list of known genetic diseases in cattle is long and still increasing and for convenience, we have herein listed only the most important. For each defect, the most characteristic findings, type of inheritance and if known also the molecular basis are given

A 6.7 kb deletion in the COL2A1 gene in a Holstein calf with achondrogenesis type II and perosomus elumbis

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Homozygosity mapping of Arachnomelia in Brown cattle"

Fifteen calves affected with arachnomelia were sampled in the Swiss and Italian Brown cattle population. Analysis of the pedigree data confirmed monogenic autosomal recessive inheritance and revealed that all affected individuals traced back to a single acknowledged carrier founder sire. Eight affected offspring and 10 available relatives were genotyped for a panel of 240 microsatellites spanning the 29 bovine autosomes. Homozygosity mapping showed homozygosity of all cases at two adjacent microsatellite markers on BTA5. For fine mapping purposes 14 additional BTA5 microsatellites were genotyped in all available cases and indicated shared homozygous haplotypes across 20 Mb among affected individuals. A second pedigree with 23 acknowledged carriers among 34 sires in total related to the founder were genotyped for these markers. Linkage and haplotype analysis showed that the arachnomelia mutation could be assigned to a 7.2 Mb candidate region (LOD score >6). The linked markers can be used for indirect determination of the arachnomelia genotype in offspring of related carrier sires. This bovine chromosome segment corresponds to an ortholog segment of HSA12q containing more than 140 annotated genes and loci. The only obvious functional candidate gene of this region GDF11 is probably not responsible for this fatal bovine disorder

Identification of a missense mutation in the bovine ATP2A1 gene in congenital pseudomyotonia of Chianina cattle: An animal model of human Brody disease

Congenital pseudomyotonia in Chianina cattle is a muscle function disorder very similar to that of Brody disease in humans. Mutations in the human ATP2A1 gene, encoding SERCA1, cause Brody myopathy. The analysis of the collected Chianina pedigree data suggested monogenic autosomal recessive inheritance and revealed that all 17 affected individuals traced back to a single founder. A deficiency of SERCA1 function in skeletal muscle of pseudomyotonia affected Chianina cattle was observed as SERCA1 activity in affected animals was decreased by about 70%. Linkage analysis showed that the mutation was located in the ATP2A1 gene region on BTA25 and subsequent mutation analysis of the ATP2A1 exons revealed a perfectly associated missense mutation in exon 6 (c.491GNA) leading to a p.Arg164His substitution. Arg164 represents a functionally important and strongly conserved residue of SERCA1. This study provides a suitable large animal model for human Brody disease

ELLIS-VAN CREVELD (EVC-2) SYNDROME IN TYROLEAN GREY CATTLE: MORPHOLOGICAL STUDY OF A TYPE OF CHONDRODYSPLASTIC DWARFISM.

Ellis-van Creveld (EVC2) syndrome has been first described in children and is a complex clinical syndrome that presents with short limbs, retarded growth, polydactyly, ectodermal and heart defects and ciliopathies. This syndrome is due to a mutation of EVC2 gene (1). The aim of this study was to describe the gross and histological features of bovine chondrodysplastic dwarfism (CD) with deletion of EVC2 gene. Four calves (3 female and one male) aged 2 to 5 months, with a clinical diagnosis of CD, were subjected to necropsy. The same cases were included in a whole genomic re-sequencing study that confirmed the deletion of the EVC2 gene (2). Bones, ligaments, heart and genital tract were routinely processed. Sections were stained with H&E. At necropsy, the limbs of all the subjects were disproportionately short and bulky, rotated and arched in a \u201cdumbbell-like\u201d position. The long bones were severely reduced in length, with a very short diaphysis. In the 3 female calves, despite the young age, the genital tract was fully developed. In one case endocardiosis of the atrioventricular valves was observed. Histologically, the growth plates were irregular and closed prematurely. The reserve zone was variably thickened at the expense of proliferative and hypertrophic zones. Chondrocytes in the latter zones were disorganized, had multifocal loss of normal columnar arrangement, and were haphazardly arranged individually or in nests. The metaphysis was reduced in length, and the trabeculae in the primary spongiosa were shortened. Ovaries had follicles and corpora lutea; ligaments occasionally had multifocal lymphoplasmacytic inflammation. CD due to an autosomal recessive mutation of the Limbin gene was described for the first time in the Japanese brown breed (3). A genetic study on inherited chondrodysplasia due to EVC2 deletion was recently reported in Tyrolean grey cattle (2), and now we describe the pathological aspects of EVC2 in this breed. As in humans, where EVC2 involves multiple organs, one of our cases showed endocardiosis. No genital lesions have been reported so far in human EVC2. EVC2 syndrome in Tyrolean Grey cattle is characterized by CD, genital and heart defects and could be a useful model for human medicine. 1. Kamal et al., J Oral Maxillofac Pathol. 2013, 17:132-5. 2. Murgiano et al., Plos one 2014, In press 3. Takeda et al., Proc Natl Acad Sci U S A. 2002, 6;99:10549-54 ANATOMIA PATOLOGICA Calf , EVC2 syndrome , chondrodysplasi

Preliminary pathological results on chondrodysplastic dwarfism in Tyrolean Grey cattle due to deletion in the EVC2 gene

Preliminary pathological results on chondrodysplastic dwarfism in Tyrolean Grey cattle due to deletion in the EVC2 gene C Benazzi*, KE Dittmer\u2020, KG Thompson\u2020, C Dr\uf6gem\ufcller\u2021, A Gentile*, LV Muscatello*, L Murgiano\u2021, C Piffer#, M Bolcato* and B Brunetti* *Department of Veterinary Medical Sciences, University of Bologna, 40064 Ozzano dell\u2019Emilia, Italy. Email: [email protected] \u2020Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand \u2021Institute of Genetics, Vetsuisse Faculty, University of Bern, 3001 Bern, Switzerland. #Gesundheitbezirk Bozen, Laura Conti Strasse 4, 39100 Bozen, Italy. During July\u2013November 2013 breeders reported the birth of Italian Tyrolean Grey calves with abnormally short limbs. Seven calves, aged 2\u20135 months, were referred to the Department of Veterinary Medical Sciences, Bologna, Italy. Whole genome resequencing of an affected calf detected a single candidate causal mutation in the Ellis van Creveld syndrome 2 (EVC2) gene. All animals had difficulties in assuming or maintaining a quadrupedal stance, with deterioration in this ability with increased growth. The limbs were disproportionately short and bulky, variably rotated and arched in a dumbbell-like position. At necropsy, the limbs (in particular the femur and humerus) were rotated and significantly shortened. Histologically the growth plates of long bones and vertebrae were irregular and prematurely closed. The reserve zone showed variable thickness at the expense of proliferative and hypertrophic zones, which were disorganised with multifocal loss of the normal columnar arrangement. In one calf reduced development of the heart valves was noted. In three female calves the genital tracts appeared fully mature, with numerous follicle-like structures on the ovaries. The uteri had multiple polypoid structures

Arachnomelia in Brown Swiss cattle maps to chromosome 5

Arachnomelia in Brown Swiss cattle is a monogenic autosomal recessive inherited congenital disorder of the skeletal system giving affected calves a spidery look (OMIA ID 000059). Over a period of 20 years 15 cases were sampled in the Swiss and Italian Brown cattle population. Pedigree data revealed that all affected individuals trace back to a single acknowledged carrier founder sire. A genome scan using 240 microsatellites spanning the 29 bovine autosomes showed homozygosity at three adjacent microsatellite markers on bovine Chr 5 in all cases. Linkage analysis confirmed the localization of the arachnomelia mutation in the region of the marker ETH10. Fine-mapping and haplotype analysis using a total of 34 markers in this region refined the critical region of the arachnomelia locus to a 7.19-Mb interval on bovine Chr 5. The disease-associated IBD haplotype was shared by 36 proven carrier animals and allows marker-assisted selection. As the corresponding human and mouse chromosome segments do not contain any clear functional candidate genes for this disorder, the mutation causing arachnomelia in the Brown Swiss cattle might help to identify an unknown gene in bone development