Genetic location of MHC Major Histocompatibility Complex (MHC) genes are clustered on which chromosomes in humans and in mice, respectively?

Introduction / Context:
The Major Histocompatibility Complex encodes molecules that present antigenic peptides to T cells and shape immune responses. Knowing the chromosomal location of the MHC is fundamental for genetics, transplantation biology, and disease association studies (HLA typing in humans).

Given Data / Assumptions:

• Human MHC is called HLA (Human Leukocyte Antigen).
• Mouse MHC is called H-2.
• We are asked for chromosomal locations in each species.

Concept / Approach:

The HLA complex resides on human chromosome 6 (short arm, 6p21). The murine H-2 complex is on mouse chromosome 17. These loci are highly polymorphic and include class I (A, B, C in humans), class II (DP, DQ, DR), and class III regions. Their gene products are central to antigen presentation and graft compatibility.

Step-by-Step Solution:

Verification / Alternative check:

Standard immunology references and genetic maps place HLA on 6p21 and H-2 on mouse 17, widely used in synteny and QTL studies.

Why Other Options Are Wrong:

• Other chromosome pairings invert or misassign species.
• Chromosome 1 for both species is incorrect for MHC.

Common Pitfalls:

• Confusing numerical chromosome labels between species; remember “6 for HLA, 17 for H-2.”

Final Answer:

Chromosome 6 in humans, chromosome 17 in mice