HLA-B57
Encyclopedia
HLA-B (alpha)-β2MG with bound peptide
Alleles *5701, *5702, *5703, *5704
Structure (See HLA-B
HLA-B
HLA-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 complex...

)
Shared data
Locus
Locus (genetics)
In the fields of genetics and genetic computation, a locus is the specific location of a gene or DNA sequence on a chromosome. A variant of the DNA sequence at a given locus is called an allele. The ordered list of loci known for a particular genome is called a genetic map...

chr.6
Chromosome 6 (human)
Chromosome 6 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 6 spans more than 170 million base pairs and represents between 5.5 and 6% of the total DNA in cells...

 6p21.31


HLA-B57 (B57) is an HLA
Human leukocyte antigen
The human leukocyte antigen system is the name of the major histocompatibility complex in humans. The super locus contains a large number of genes related to immune system function in humans. This group of genes resides on chromosome 6, and encodes cell-surface antigen-presenting proteins and...

-B
HLA-B
HLA-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 complex...

 serotype
Serotype
Serotype or serovar refers to distinct variations within a subspecies of bacteria or viruses. These microorganisms, viruses, or cells are classified together based on their cell surface antigens...

. B57 is a split antigen from the B17
HLA-B17
HLA-B17 is an HLA - B serotype. B17 is a broad antigen serotype that recognizes the B57 and B58 split antigen serotypes. B17 is still encountered in the current literature, although most studies now use B57/B58 or gene typing designators. Both serotypes are involved in slightly different...

 broad antigen, the sister serotype B58
HLA-B58
HLA-B58 is an HLA-B serotype. B58 is a split antigen from the B17 broad antigen, the sister serotype B57. The serotype identifies the more common HLA-B*58 gene products...

. The serotype identifies the more common HLA-B*58 gene products. (For terminology help see: HLA-serotype tutorial) Like B58, B57 is involved in drug-induced inflammatory skin disorders.

Serotype

B57 and B17 serotype recognition of some more common HLA B*57 alleles
B*57 B57 B17 Sample
allele % % size (N)
92 5 3670
78 8 65
85 6 412
67 7 32

Allele distribution

HLA B*5701 frequencies
freq
ref. Population (%)
South Africa Natal Tamil 10.2
India Tamil Nadu Nadar 8.2
Spain E. Andalusia Gipsy 7.1
Ireland South 5.8
India North Delhi 4.9
India New Delhi 3.8
Ireland Northern 3.8
Azores Central Islands 3.6
Cuban White 3.6
France South East 3.5
China Guangzhou Han 3.3
China North Han 3.3
Czech Republic 3.3
Russia Tuva (2) 3.3
Cape Verde NW Islands 3.2
Azores Terceira Island 3.1
Portugal South 3.1
Thailand (3) 3.1
Uganda Kampala 3.1
Portugal Centre 3.0
Tunisia 3.0
India Andhra Pradesh Golla 2.9
Belgium 2.0
China Inner Mongolia 2.0
Croatia 2.0
SP Javanese Indonesians 2.0
Singapore Riau Malay 2.0
India North Hindus 1.9
Bulgaria 1.8
Thailand 1.8
Finland 1.7
Macedonia pop 4 1.6
Madeira 1.6
Indig. Australian Cape York Penin. 1.5
Israel Arab Druse 1.5
Sudanese 1.5
Morocco Nador Metalsa (Berber) 1.4
Oman 1.3
Mexico Mestizos 1.2
Zambia Lusaka 1.1
Shijiazhuang Tianjian Han 1.0
Iran Baloch 1.0
USA Asian 1.0


HLA B*5702 frequencies
freq
ref. Population (%)
Zambia Lusaka 2.3
Senegal Niokholo Mandenka 1.6
Kenya 1.4
Mali Bandiagara 1.1
South Africian Natal Zulu 1.0
B*5703
Zambia Lusaka 5.7
Cameroon Bakola Pygmy 5.0
Ivory Coast Akan Adiopodoume 4.6
Zimbabwe Harare Shona 4.4
South Africian Natal Zulu 4.0
Cameroon Bamileke 3.2
Cameroon Beti 3.2
Kenya Nandi 2.9
Israel Ashk. & Non-Ashk. Jews 2.8
Cameroon Yaounde 2.7
Tunisia Tunis 2.3
Saudi Arabia Guraiat and Hail 1.5

Disease

HLA-B*5701 is associated with drug-induced inflammatory disease of the skin. Individuals with B57 are more sensitive to the drug abacavir
Abacavir
Abacavir is a nucleoside analog reverse transcriptase inhibitor used to treat HIV and AIDS. It is available under the trade name Ziagen and in the combination formulations Trizivir and Kivexa/Epzicom...

. Abacavir is an antiretroviral drug
Antiretroviral drug
Antiretroviral drugs are medications for the treatment of infection by retroviruses, primarily HIV. When several such drugs, typically three or four, are taken in combination, the approach is known as Highly Active Antiretroviral Therapy, or HAART...

 used in treatment of HIV
HIV
Human immunodeficiency virus is a lentivirus that causes acquired immunodeficiency syndrome , a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive...

, however in sensitive individuals fever, skin rash, fatigue, gastrointestinal symptoms such as nausea, vomiting, diarrhea or abdominal pain and respiratory symptoms such as pharyngitis, dyspnea, or cough can develop. FDA has advised that people from at-risk ethnic groups, (see table on the left) be screened prior to drug-therapy.
[Note: phenotype frequencies are roughly double allele frequencies -tabled values- when allele frequency is less than 30%]
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