Thyroid Hormone Receptor Beta (TRβ) is a protein that binds to thyroid hormones, which are crucial for regulating metabolism, growth, and development in the body. It is one of two main types of thyroid hormone receptors, the other being Thyroid Hormone Receptor Alpha (TRα). TRβ is primarily found in the brain, heart, and liver, where it helps modulate gene expression in response to thyroid hormones. TRβ plays a significant role in maintaining normal physiological functions. Mutations or dysfunctions in the TRβ gene can lead to various health issues, including resistance to thyroid hormone syndrome, which affects how the body responds to thyroid hormones. Understanding TRβ is essential for developing treatments for thyroid-related disorders.