Genetic Predictors of Brachydactyly in Miniature Pinschers: Rationale for Implementing DNA Screening of the ROR2, BMPR1B and DVL2 Loci

Abstract Background. Hereditary anomalies of limb skeletal development in dogs present a significant challenge for modern purebred breeding programs. In the Miniature Pinscher population, cases of digital phalanx shortening and deformity (brachydactyly) are routinely documented. However, in veterinary practice, this phenotype is frequently misclassified as an isolated cosmetic flaw or a consequence of early trauma, leading to systematic neglect of the issue and uncontrolled dissemination of the underlying pathology within the breed. Objectives. To establish a scientific rationale for the polyetiological genetic nature of brachydactyly in Miniature Pinschers and to demonstrate the necessity of implementing preventative DNA screening protocols. Hypothesis. This paper presents the first comprehensive rationale linking distal limb deformities in Miniature Pinschers to the cryptic carriage of mutations within four key loci: ROR2, BMPR1B, DVL2. The author analyzes the specific molecular mechanisms underlying these defects, differentiating isolated forms of brachydactyly (types B and A2) from severe syndromic conditions (Robinow-like syndrome) that can induce life-threatening axial skeletal anomalies (IVDD, hemivertebrae) and congenital heart defects. Practical Significance. Based on the theoretical framework, a step-by-step interpretation algorithm for DNA test results and a specialized selective mating matrix for breeders are proposed. Implementing the suggested testing panel will enable the timely elimination of deleterious alleles from the core breeding population while preserving the broader genetic diversity of the Miniature Pinscher breed. Keywords: Miniature Pinscher, brachydactyly, ROR2, BMPR1B, DVL2, Robinow-like syndrome, DNA screening, veterinary genetics.