Clinical and molecular study of a new form of congenital stationary night blindness in horses

• Grant number: 24/03861-1
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2024
• End date: July 31, 2026
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Alexandre Secorun Borges
• Grantee: Alexandre Secorun Borges
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated researchers: João Pessoa Araújo Junior ; José Paes de Oliveira Filho ; Paulo Aléscio Canola

Abstract

Genetic diseases in horses are highly relevant to health and have been the subject of significant studies. Over the past 30 years, several diseases have been described, and with the characterization of the pathogenic variant, control measures could be employed to prevent the spread of these variants in the population. Despite the decreasing costs of genetic variant assessment through large-scale sequencing, the characterization of variants and their association with the phenotype is not straightforward. Some may have a multifactorial etiology or involve variants not described in other species. A new hereditary form of congenital stationary night blindness, not associated with previously described variants, has affected horses from different breeding farms in the states of São Paulo and Minas Gerais. This condition has caused losses due to the birth of animals with a significant reduction in visual acuity that worsens in low light conditions. This study aims to characterize clinically and molecularly this new form of congenital stationary night blindness in Mangalarga Marchador horses. Clinically affected animals will be selected for ophthalmological examination, and those with abnormalities will undergo whole-genome sequencing to identify candidate genes. These genes will be reassessed in affected animals and in a control population of horses to identify the causal gene for this condition and provide a diagnostic test that will prevent the spread of the causal variant in the horse population. (AU)