Comparação dos transcriptomas da cartilagem e da placa de crescimento do fêmur de frangos de corte normais e afetados com necrose de cabeça de fêmur

Abstract

The Femoral Head Separation (FHS) is usually a subclinical condition characterized by the detachment of articular cartilage from the bone. This condition is closely related to Femoral Head Necrosis (FHN), one of the main locomotor problems that affect the poultry production. Therefore, in this study, a comprehensive analysis identifying shared expression profiles, biological processes (BP) and variants related to FHS and subsequent FHN in chickens was performed through RNA sequencing analysis. To this, two datasets containing 8 normal and 8 FHS-affected transcriptomes from broilers femoral articular cartilage (AC) and growth plate (GP) were analyzed. Furthermore, we have compared the differential gene expression found in FHS-chickens with other datasets available in public databases, trying to clarify shared genes and biological processes related to FHN in different species. A total of 36 differentially expressed (DE) genes were shared between AC and GP tissues, where more than 90% was upregulated in the FHS-affected broilers. Out of those, 23 genes were enriched in BP related to ion transport, translation factors and immune response. When the chicken DE genes were compared to other FHN datasets, 8 genes were shared among the evaluated species with normal and FHN affected samples: SLC4A1, EPB42, ANK1, SPTB, CCL26, ADA, SLC25A37 and MKNK2. This study found DE genes between normal and FHS-affected broilers common to both analyzed tissues, showing shared mechanisms involved with this condition in chickens. Comparing the AC and GP DE genes with other datasets related to FHN allowed us to identify genes that are possibly involved with FHN across different species. We were able to find strong candidate genes related to FHS and FHN in chickens, such as SLC4A1, RHAG, ANK1, MKNK2, SPTB, ADA, C7 and EPB420. The role of these genes should be more explored in order to validate them as genetic markers to select against FHS/FHN, as well as improving the information available regarding the etiology of these conditions in chickens and possibly in humans.