The promoter region of interferon-gamma is hypermethylated in neonatal foals and its demethylation is associated with increased gene expression.

The researchers focused on the gene expression of interferon-gamma (IFN-γ) in neonatal foals. They found that environmental factors, such as barn-air exposure, and the animal’s age influenced the methylation status of the promoter region of this gene and subsequently its expression levels.

Understanding Interferon-gamma and DNA Methylation

• The study is centered on the gene expression of Interferon-gamma (IFN-γ), a type of protein in neonatal foals, which are young horses. Though newborn foals have limited production of IFN-γ, its expression increases after birth.
• DNA methylation is involved in the regulation of gene expression. In this context, it’s important to note that methylation is when a methyl group is added to a DNA molecule. When this happens to the promoter region, it can inhibit gene expression. Hence, methylation is an important aspect in gene regulation and cellular differentiation.

Methylation of Interferon-gamma in Foals

• The researchers analyzed the methylation status of the Ifng promoter in the CD4(+) cells from the neonatal foal. They did this using a method called methylation-specific PCR (MSP). The Ifng promoter region refers to the sequence of DNA that initiates transcription of the Ifng gene.
• Results found that the DNA in the Ifng promoter was hypermethylated in the foals. Hypermethylation usually leads to the silencing of gene expression. This hypermethylation was found to decrease as the foal grew older.

Environmental Influence and Implications

• Interestingly, the rate of this age-associated demethylation was found to speed up when the foals were exposed to barn-air. This gave researchers an understanding that exposure to certain environmental factors could potentially accelerate the demethylation process.
• The effect of DNA methylation and demethylation on the gene expression of IFN-γ suggests that this could be a mechanism controlling the IFN-γ expression in foals.
• The researchers conclude that the age-associated demethylation of the DNA in foals may be induced by exposure to environmental factors. This opens new considerations for how environmental antigens might impact lymphoproliferation, the rapid production of lymphocytes, a type of white blood cell that plays an important role in the body’s immune response.