Description of the D4/D4 genotype in Miniature horses with dwarfism

Autor(es)

Andrade, Danilo G. A. ^[1] ; Basso, Roberta M. ^[1] ; Castiglioni, Maria C. R. ^[1] ; Silva, Jeana P. ^[1] ; Machado, Vania M. V. ^[1] ; Laufer-Amorim, Renee ^[1] ; Borges, Alexandre S. ^[1] ; Oliveira-Filho, Jose P. ^[1]

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ Unesp, Sch Vet Med & Anim Sci, Dept Vet Clin Sci, BR-18618681 Botucatu, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF VETERINARY DIAGNOSTIC INVESTIGATION; v. 32, n. 1 JAN 2020.
• Citações Web of Science: 0

Resumo

Four causative mutations (D1, D2, D3{*}, and D4) of chondrodysplastic dwarfism have been described in the equine aggrecan (ACAN) gene. Homozygotes for one of these mutations and heterozygotes for any combination of these mutations exhibit the disproportionate dwarfism phenotype. However, no case description of homozygotes for D4 (D4/D4) has been reported in the literature, to our knowledge. We report 2 Miniature horses with the genotype D4/D4 in the ACAN gene. Clinically, the 2 dwarfs had a domed head that was large compared to the rest of the body, mandibular prognathism, and short and bowed limbs, mainly in the proximal region of the metatarsal bones. Radiographic examination revealed contour irregularities of the subchondral bone in the long bones and confirmed mandibular prognathism; histopathology revealed irregular chondrocyte organization. To determine the genotypes of the horses, we performed DNA extraction from white blood cells, PCR, and Sanger sequencing. Genotyping demonstrated that these 2 animals had the D4/D4 genotype in the ACAN gene. The D4/D4 dwarfs were clinically similar to animals with the other ACAN genotypes reported for this disease. Identification of heterozygous animals makes mating selection possible and is the most important control measure to minimize economic losses and casualties. (AU)

• Processo FAPESP: 16/24767-7 - Estudo clínico e molecular do nanismo do tipo condrodisplásico em equinos da raça Mini-Horse no Brasil
• Beneficiário: José Paes de Oliveira Filho
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 16/24025-0 - Avaliação das mutações causadoras do nanismo do tipo condrodisplásico em equinos da raça Mini-Horse no Brasil
• Beneficiário: Danilo Giorgi Abranches de Andrade
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 18/11365-3 - Estudo da proteína agrecano e do padrão de citocinas associado ao nanismo em equinos da raça Mini-horse no Brasil
• Beneficiário: Roberta Martins Basso
• Modalidade de apoio: Bolsas no Brasil - Mestrado