HLA allele associated with Graves disease is

**Core Concept**
Graves' disease is an autoimmune disorder characterized by hyperthyroidism, resulting from autoantibodies targeting the thyroid-stimulating hormone receptor (TSHR). The human leukocyte antigen (HLA) system plays a crucial role in the immune response, and specific HLA alleles are associated with an increased risk of developing autoimmune diseases.

**Why the Correct Answer is Right**
The HLA allele associated with Graves' disease is HLA-DRB1*0301. This allele is linked to an increased expression of CD4+ T cells, which are pivotal in the pathogenesis of Grave's disease. The CD4+ T cells stimulate B cells to produce autoantibodies against the TSHR, leading to the overproduction of thyroid hormones. The HLA-DRB1*0301 allele is more prevalent in individuals with Graves' disease, suggesting its role in the disease's pathogenesis.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it is not associated with Graves' disease.
**Option B:** This option is incorrect as it is more commonly linked to ankylosing spondylitis and other spondyloarthropathies.
**Option C:** This option is incorrect as it is associated with type 1 diabetes mellitus and other autoimmune conditions, but not specifically with Graves' disease.

**Clinical Pearl / High-Yield Fact**
HLA-DRB1*0301 is a significant risk factor for developing Graves' disease, particularly in individuals with a family history of the disease. This knowledge is essential for clinicians to identify high-risk patients and implement preventive measures.

**Correct Answer: D. HLA-DRB1*0301**