HLA -A, B, C belongs to which class of HLA Complex of genes located on 6th chromosome
**Core Concept**
The HLA (Human Leukocyte Antigen) complex is a group of genes that play a crucial role in the immune system's ability to distinguish between self and non-self. The HLA-A, B, and C genes are part of the class I region of the HLA complex, which is involved in the presentation of peptide fragments from inside the cell to T-cells.
**Why the Correct Answer is Right**
The HLA-A, B, and C genes are located on the short arm of chromosome 6 (6p21.3) and are responsible for encoding class I MHC (Major Histocompatibility Complex) molecules. These molecules present peptide fragments from inside the cell to CD8+ T-cells, which helps to activate an immune response against infected cells or tumor cells. The class I region of the HLA complex is highly polymorphic, meaning that there is a wide range of variations in the genes that encode the HLA-A, B, and C molecules.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the HLA-A, B, and C genes are not located on chromosome 1.
**Option B:** This option is incorrect because the HLA-A, B, and C genes are not located on chromosome 9.
**Option C:** This option is incorrect because the HLA-A, B, and C genes are not located on chromosome 10.
**Clinical Pearl / High-Yield Fact**
The HLA complex is a critical component of the immune system, and variations in the HLA genes can lead to increased susceptibility to certain diseases, such as autoimmune disorders and infections. For example, individuals with certain HLA genotypes are at increased risk of developing rheumatoid arthritis or type 1 diabetes.
**Correct Answer: D. HLA complex is located on the 6th chromosome.**