Prevalence of elbow dysplasia in 13 dog breeds in France: a retrospective radiographic study (2002-2022).

OBJECTIVE: To describe the prevalence of elbow dysplasia (ED) in 13 dog breeds in France. ANIMALS: A total of 18,870 elbow radiographs taken from 2002 to 2022 were evaluated by 2 independent examiners. METHODS: For each breed, the incidence of each of the 4 International Elbow Working Group scoring classes was extracted from the database. Breeds were excluded if fewer than 150 radiographs had been read for that breed. RESULTS: This study included 17,861 records for 13 dog breeds: American Akita, Alaskan Malamute, Old German Shepherd (Altdeutscher Schäferhund), American Staffordshire Terrier, Australian Shepherd, Belgian Shepherd, White Swiss Shepherd, Bernese Mountain Dog, Cane Corso, Czechoslovakian Wolfdog, Rhodesian Ridgeback, Rottweiler, and Dogue de Bordeaux. The overall prevalence of ED was 11.4%, ranging from 1.1% in the Czechoslovakian Wolfdog to 32.2% in the Dogue de Bordeaux. The Dogue de Bordeaux, Rottweiler, Bernese Mountain Dog, and Cane Corso breeds were most commonly affected by ED. The prevalence of ED was significantly higher in male dogs than in female dogs (17.5% vs 10.5%, P < .05). Joint incongruity and fragmented coronoid process were the 2 most common primary ED lesions identified. The prevalence of ED among the dogs evaluated decreased over the timeframe of the study. CLINICAL RELEVANCE: The results of this study help to clarify the prevalence of ED in different breeds in France. These data should be interpreted with caution as this study included a small percentage of the total number of dogs born for each breed in France over the study period.

Novel ADGRG2 truncating variants in patients with X-linked congenital absence of vas deferens.

BACKGROUND: Congenital absence of vas deferens (CAVD) represents a major cause of obstructive azoospermia and is mainly related to biallelic alteration of the CFTR gene, also involved in cystic fibrosis. Using whole exome sequencing, we recently identified hemizygous loss-of-function mutations in the Adhesion G Protein-coupled Receptor G2 gene (ADGRG2) as responsible of isolated CAVD in the absence of associated unilateral renal agenesis. OBJECTIVES: The objective of this study was to retrospectively perform ADGRG2 sequencing on a large cohort of patients with CAVD, and 0 or only 1 CFTR defective allele identified after comprehensive testing in order to (a) define more precisely the spectrum and the frequency of ADGRG2 mutations within Caucasian population (b) explore the possibility of co-occurrence of CFTR and ADGRG2 mutations. MATERIALS AND METHODS: We collected 53 DNA samples from CAVD patients with 0 (n = 23) or 1 (n = 30) alteration identified after comprehensive CFTR testing in order to perform ADGRG2 sequencing. Twenty patients had normal ultrasonographic renal examination, and renal status was not documented for 33 patients. RESULTS: We identified six new truncating ADGRG2 mutations in 8 patients including two twin brothers: c.251C > G (p.Ser84*), c.1013delC (p.Pro338Hisfs*4), c.1460delG (p.Gly487Alafs*9), c.2096dupT (p.Phe700Ilefs*29), c.2473C > T (p.Arg825*), and c.1731_1839 + 373del (p.Asn578Thrfs*12), which is a 596 base pair deletion affecting the last five bases of exon 21 and the whole exon 22. Five of the eight patients also harbored an heterozygous CFTR mutation which we consider as incidental regarding the high penetrance expected for ADGRG2 truncating variants. The frequency of ADGRG2 truncating mutation was 26% (5/19 unrelated patients) when presence of both kidneys was attested by ultrasonography and 6.1% (2/33) among patients with unknown renal status. DISCUSSION & CONCLUSION: Our results confirm the interest of ADGRG2 sequencing in patients with CAVD not formerly related to CFTR dysfunction, especially in the absence of associated unilateral renal agenesis.