الفهرس 
Solving the mysteryOnly 14 pages are availabe for public view
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Abstract
HLA Solving The Mystery
The major histocompatibility complex (MHC) was discovered
more than 50 years ago. Several decades of intensive research has defined
the remarkable genomic environment of the MHC and how genetic
variation within this region plays a key role in susceptibility to
autoimmune, infectious and other diseases.
In this review, rather than describing specific MHC associated
diseases, we recall the historical context and describe the genomic
landscape of the MHC and some of the challenges which remain: an
ongoing adventure in exploring human genetic diversity that keeps the
MHC at the forefront of research in human genomics.
1.1 MHC and HLA : basic facts
The (MHC) is a large gene complex present in all jawed
vertebrates with an integral role in the immune system. The antigenpresenting
molecules encoded by the MHC class I and class II genes are
cell-surface glycoproteins that bind intracellular & extracellular peptides,
respectively (Mosaad et al., 2015).
These antigens play predominant role in acceptance or rejection of
transplanted organs - so they are called as histocompatibility antigens
(Arpita et al., 2014).
The term HLA stands for human leucocyte antigens as these
antigens were initially detected on the leucocytes (Dunn, 2011).
It is equivalent to murine H-2 complex. The HLA class I and class
II genes are known as the most polymorphic genes in the human genome.
The remarkable extent of the allelic diversity at these loci has been
revealed over the past three decades by molecular genetic analyses, made
possible by the development of recombinant DNA technology.