The canine genome

Veterinarians' Competence in Applying Basic Genetic Principles and Daily Implementation of Clinical Genetics: A Study in a University Environment

Veterinarian competency in genetics is vital for a meaningful application of the rapidly growing number of genetic tests available for animals. We evaluated the use of genetic tests in the daily veterinary practice and the competency of university-employed veterinarians in applying basic principles of genetics in a clinical setting through an electronic survey with 14 cases and 7 statements on genetics. Ninety-one non-geneticist veterinarians from two veterinary faculties in two different countries responded. Almost half of the participants apply genetic tests during their daily work, with frequencies varying between weekly and once a year. The most common indication to request a genetic test was diagnostic testing of clinically ill patients. Although 80% of the veterinarians communicated the result of a genetic test themselves, only 56% of them found it "very to rather easy" to find the correct test, and only 32% of them always felt competent to interpret the result of the test. The number of correctly answered questions varied widely, with median scores of 9/14 (range 0-14) and 5/7 (range 0-7) for the cases and statements, respectively. Most difficulties were seen with recognition of pedigree inheritance patterns, while veterinarians scored better in breeding advice and probability of disease estimations. Veterinarians scored best on questions related to autosomal recessive inheritance, followed by complex, autosomal dominant, X-linked recessive, and X-linked dominant inheritance. This study exposed pain points in veterinarians' knowledge and has led to the formulation of recommendations for future education and communication between laboratories, geneticists, and veterinarians.

Genetic diversity, inbreeding and cancer

Genetic diversity is essential for adaptive capacities, providing organisms with the potential of successfully responding to intrinsic and extrinsic challenges. Although a clear reciprocal link between genetic diversity and resistance to parasites and pathogens has been established across taxa, the impact of loss of genetic diversity by inbreeding on the emergence and progression of non-communicable diseases, such as cancer, has been overlooked. Here we provide an overview of such associations and show that low genetic diversity and inbreeding associate with an increased risk of cancer in both humans and animals. Cancer being a multifaceted disease, loss of genetic diversity can directly (via accumulation of oncogenic homozygous mutations) and indirectly (via increased susceptibility to oncogenic pathogens) impact abnormal cell emergence and escape of immune surveillance. The observed link between reduced genetic diversity and cancer in wildlife may further imperil the long-term survival of numerous endangered species, highlighting the need to consider the impact of cancer in conservation biology. Finally, the somewhat incongruent data originating from human studies suggest that the association between genetic diversity and cancer development is multifactorial and may be tumour specific. Further studies are therefore crucial in order to elucidate the underpinnings of the interactions between genetic diversity, inbreeding and cancer.

Prevalence of disorders recorded in dogs attending primary-care veterinary practices in England

Purebred dog health is thought to be compromised by an increasing occurence of inherited diseases but inadequate prevalence data on common disorders have hampered efforts to prioritise health reforms. Analysis of primary veterinary practice clinical data has been proposed for reliable estimation of disorder prevalence in dogs. Electronic patient record (EPR) data were collected on 148,741 dogs attending 93 clinics across central and south-eastern England. Analysis in detail of a random sample of EPRs relating to 3,884 dogs from 89 clinics identified the most frequently recorded disorders as otitis externa (prevalence 10.2%, 95% CI: 9.1-11.3), periodontal disease (9.3%, 95% CI: 8.3-10.3) and anal sac impaction (7.1%, 95% CI: 6.1-8.1). Using syndromic classification, the most prevalent body location affected was the head-and-neck (32.8%, 95% CI: 30.7-34.9), the most prevalent organ system affected was the integument (36.3%, 95% CI: 33.9-38.6) and the most prevalent pathophysiologic process diagnosed was inflammation (32.1%, 95% CI: 29.8-34.3). Among the twenty most-frequently recorded disorders, purebred dogs had a significantly higher prevalence compared with crossbreds for three: otitis externa (P = 0.001), obesity (P = 0.006) and skin mass lesion (P = 0.033), and popular breeds differed significantly from each other in their prevalence for five: periodontal disease (P = 0.002), overgrown nails (P = 0.004), degenerative joint disease (P = 0.005), obesity (P = 0.001) and lipoma (P = 0.003). These results fill a crucial data gap in disorder prevalence information and assist with disorder prioritisation. The results suggest that, for maximal impact, breeding reforms should target commonly-diagnosed complex disorders that are amenable to genetic improvement and should place special focus on at-risk breeds. Future studies evaluating disorder severity and duration will augment the usefulness of the disorder prevalence information reported herein.