HLA-B
HLA-B (major histocompatibility complex, class I, B) is a human gene that provides instructions for making a protein that plays a critical role in the immune system. HLA-B is part of a family of genes called the human leukocyte antigen (HLA) complex. The HLA complex helps the immune system distinguish the body's own proteins from proteins made by foreign invaders such as viruses and bacteria.

HLA is the human version of the major histocompatibility complex (MHC), a gene family that occurs in many species. Genes in this complex are separated into three basic groups: class I, class II, and class III. In humans, the HLA-B gene and two related genes, HLA-A and HLA-C, are the major genes in MHC class I.

MHC class I genes provide instructions for making proteins that are present on the surface of almost all cells. On the cell surface, these proteins are bound to protein fragments (peptides) that have been exported from within the cell. MHC class I proteins display these peptides to the immune system. If the immune system recognizes the peptides as foreign (such as viral or bacterial peptides), it responds by destroying the infected cell.

The HLA-B gene has many different normal variations, allowing each person's immune system to react to a wide range of foreign invaders. Hundreds of versions (alleles) of HLA-B are known, each of which is given a particular number (such as HLA-B27). Closely related alleles are categorized together; for example, at least 28 very similar alleles are subtypes of HLA-B27. These subtypes are designated as HLA-B*2701 to HLA-B*2728.

The HLA-B gene is located on the short (p) arm of chromosome 6 at cytoband 21.3, from base pair 31,353,871 to 31,357,211 
Q5
human
Concept
Q7187
gene
Concept
Q8054
protein
Concept
Q1059
immune system
Concept
Q911125
human leukocyte antigen
LOC
Q808
virus
Concept
Q10876
bacteria
Concept
Q423163
major histocompatibility complex
Concept
Q13218497
class I
Concept
Q959350
class II
Concept
None
class III
UNK
Q14906952
HLA-A
LOC
Q14906978
HLA-C
MISC
Q172847
peptide
Concept
Q420574
HLA-B27
MISC
Q540857
chromosome 6
MISC
Q145911
base pair
Concept
Q18026920
HLA-B
MISC
Q18026920
HLA-B
MISC
Q18026920
HLA-B
MISC
Q18026920
HLA-B
MISC
Q18026920
HLA-B
MISC
Q18026920
HLA-B
MISC
Q18026920
HLA-B
MISC
Q18026920
HLA-B
MISC
Q18026920
HLA-B
MISC
+27^^http://www.w3.org/2001/XMLSchema#decimal
27
NUMBER
+28^^http://www.w3.org/2001/XMLSchema#decimal
28
NUMBER
+27^^http://www.w3.org/2001/XMLSchema#decimal
27
NUMBER
+2701^^http://www.w3.org/2001/XMLSchema#decimal
2701
NUMBER
+2728^^http://www.w3.org/2001/XMLSchema#decimal
2728
NUMBER
+6^^http://www.w3.org/2001/XMLSchema#decimal
6
NUMBER
+21.3^^http://www.w3.org/2001/XMLSchema#decimal
21.3
NUMBER
instance of
chromosome
encodes