Question

Find the correct statement with respect to HLA system.

• A. Each individual inherit one pair of haplotype from each parent.
• B. Siblings will have identical haplotype.
• C. MHC - 1 protein present on all cells including erythrocytes.
• D. Macrophages, B-cells, dendritic cells have MHC - II protein on its surface.

Answer 1

The correct option is A Each individual inherit one pair of haplotype from each parent.

a) HLA system is also called as human leukocyte antigen system. It is a gene complex which encodes for the major histocompatibility complex (MHC) in humans. HLA haplotype is the set of histocompatibility genes that are on the same chromosome and are inherited together. Each individual inherits one pair of HLA haplotypes from each parent.

b) Each parent has 2 HLA haplotypes on the chromosomes. Hence, there are 1 in 4 chance siblings will have identical haplotype.

c) MHC I protein is present on all nucleated cells. Since erythrocytes are enucleated, they do not have MHC I proteins on them.

MHC II protein is present on surface of marcophages, monocytes and dendritic cells. These are responsible for antigen presentation to T cells.

Thus, the correct answer is 'Each individual inherit one pair of the haplotype from each parent.'