Exploring the Genetic Landscape of Vitiligo in the Pura Raza Español Horse: A Genomic Perspective.
Authors: Laseca Nora, Molina Antonio, Perdomo-González Davinia, Ziadi Chiraz, Azor Pedro J, Valera Mercedes
Journal: Animals : an open access journal from MDPI
Summary
# Vitiligo in Pura Raza Español Horses: A Genomic Analysis Vitiligo, an autoimmune depigmentation disorder causing patchy loss of skin colour, occurs with notably higher frequency in grey horses, yet its genetic basis remains poorly understood. Researchers conducted a genome-wide association study across 2,359 Pura Raza Español horses genotyped with high-density SNP arrays, analysing 60,136 genetic variants to identify regions associated with vitiligo affecting three anatomical sites (eyes, mouth, nostrils), each graded for severity. One significant locus was discovered near the eyes, eight around the mouth, and seven around the nostrils; the nasal regions showed the strongest genetic effects, with candidate genes implicated in melanocyte function, skin biology, immune regulation, and tumour suppression emerging as key players in disease pathogenesis. For breeding programmes, these findings provide actionable genomic markers that could reduce vitiligo incidence through selective breeding decisions, whilst clarifying the polygenic and immunological nature of what had previously been considered purely cosmetic depigmentation. Practitioners managing grey horses should note that whilst genetic predisposition now has clearer definition, further investigation into gene-environment interactions and the precise immunological mechanisms triggering melanocyte loss will be essential before clinical preventive strategies can be fully optimised.
Read the full abstract on PubMed
Practical Takeaways
- •Breeders of Pura Raza Español horses can now use genomic markers to implement selective breeding strategies to reduce vitiligo incidence in their populations
- •Vitiligo is particularly prevalent in grey-coated horses; owners and veterinarians should monitor eyes, mouth, and nostrils as primary affected sites
- •Understanding the genetic basis of vitiligo may facilitate development of targeted interventions and improve breeding decisions to minimize this cosmetically and potentially physiologically problematic condition
Key Findings
- •Genome-wide association study identified 16 significant genomic regions associated with vitiligo in Pura Raza Español horses: 1 region around eyes, 8 around mouth, and 7 around nostrils
- •Vitiligo-like depigmentation was phenotyped in nine categories with three severity grades (absent, slight, severe) based on visual inspection of affected areas
- •Candidate genes identified relate to melanocytes, skin, immune system, tumor suppression, metastasis, and cutaneous carcinoma pathways
- •Genomic regions around the nostrils explained the highest percentage of variance in vitiligo susceptibility