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HLA-A19
HLA-A19 (A19) is a broad antigen HLA- A serotype A serotype or serovar is a distinct variation within a species of bacteria or virus or among immune cells of different individuals. These microorganisms, viruses, or cells are classified together based on their surface antigens, allowing the epi ... that may recognize the A29, A30, A31, A32, A33, and A74 serotypes. While these haplotypes are found all over the globe their combined frequencies are higher in Sub Saharan Africa, frequencies tend to decline away from Africa. References {{HLA-A serotypes 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Leukocyte Antigen
The human leukocyte antigen (HLA) system or complex is a complex of genes on chromosome 6 in humans which encode cell-surface proteins responsible for the regulation of the immune system. The HLA system is also known as the human version of the major histocompatibility complex (MHC) found in many animals. Mutations in HLA genes may be linked to autoimmune disease such as type I diabetes, and celiac disease. The HLA gene complex resides on a 3 Mbp stretch within chromosome 6, p-arm at 21.3. HLA genes are highly polymorphic, which means that they have many different alleles, allowing them to fine-tune the adaptive immune system. The proteins encoded by certain genes are also known as ''antigens'', as a result of their historic discovery as factors in organ transplants. HLAs corresponding to MHC class I ( A, B, and C), all of which are the HLA Class1 group, present peptides from inside the cell. For example, if the cell is infected by a virus, the HLA system brings fragme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HLA-A
HLA-A is a group of human leukocyte antigens (HLA) that are encoded by the HLA-A locus, which is located at human chromosome 6p21.3. HLA is a major histocompatibility complex (MHC) antigen specific to humans. HLA-A is one of three major types of human MHC class I transmembrane proteins. The others are HLA-B and HLA-C. The protein is a heterodimer, and is composed of a heavy α chain and smaller β chain. The α chain is encoded by a variant HLA-A gene, and the β chain (β2-microglobulin) is an invariant β2 microglobulin molecule. The β2 microglobulin protein is encoded by the B2M gene, which is located at chromosome 15q21.1 in humans. MHC Class I molecules such as HLA-A are part of a process that presents short polypeptides to the immune system. These polypeptides are typically 7-11 amino acids in length and originate from proteins being expressed by the cell. There are two classes of polypeptide that can be presented by an HLA protein: those that are supposed to be expressed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotype
A serotype or serovar is a distinct variation within a species of bacteria or virus or among immune cells of different individuals. These microorganisms, viruses, or cells are classified together based on their surface antigens, allowing the epidemiologic classification of organisms to the subspecies level. A group of serovars with common antigens is called a serogroup or sometimes ''serocomplex''. Serotyping often plays an essential role in determining species and subspecies. The ''Salmonella'' genus of bacteria, for example, has been determined to have over 2600 serotypes. ''Vibrio cholerae'', the species of bacteria that causes cholera, has over 200 serotypes, based on cell antigens. Only two of them have been observed to produce the potent enterotoxin that results in cholera: O1 and O139. Serotypes were discovered by the American microbiologist Rebecca Lancefield in 1933. Role in organ transplantation The immune system is capable of discerning a cell as being 'self' or 'n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HLA-A31
There is substantive false reaction of A30 with A*3101, otherwise serological identification is good. Distribution Haplotypes Examination of A31 haplotypes reveals a probable connection across northern Eurasia during the prehistoric period. Frequencies of the more 'tale-tell' haplotypes (A31-B60, B61, and B62) fall from NE to SW Europe. Other haplotypes appears to have spread from the Middle East (A31-B51 and A31-B35). References {{HLA-A serotypes 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HLA-A32
Distribution A32 is most common around the Persian Gulf and the Mediterranean Basin. It has a consistent presence in Europe. The A32 frequencies in the more isolated (genetically) peoples of Europe suggests that the A32 rise in the Mediterranean may only be partially attributable to recent migrations from the middle eastern region. There is a node in southern Europe around the Ionian Sea in which specific, European, A32-haplotypes are elevated. Haplotypes A common A32 haplotype A*3201-B*5101 can be found in Oman, United Arab Emirates, SE Iran, Bulgaria, and Portugal. A second, A*3201-B*3501 can be in the Omani, UAE, and Portugal. References {{HLA-A serotypes 3 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HLA-A33
A33 frequencies A33 shows two different distributions that can be discriminated by subtyping capability of SSP-PCR. A*3301 distribution The first distribution appears to have a Western distribution that introgresses into Europe as a result of the Post-neolithic periods. It is commonly found in linkage disequilibration within the A*3301-Cw*0802-B*1402 haplotype which can be extended to DRB1 and DQB1 in certain instances (See Below). The source of its general expansion appears to be the middle east or the levant, as it is found in the Palestinian population. B14 splits into B64 (B*1401) and B65 (B*1402) but the only Arabian people which show both antigens are the United Arab Emirates. A*3303 distribution Certain alleles confound population histories. At the top of that list is A*3303. This allele appears to jump, figuratively, out of West Africa into South Asia. The point of origin is Africa, most likely central or western Africa given the low levels in East Africa (altho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HLA-A74
Disease associations A significant association has been found between A74 and nasal polyposis Nasal polyps (NP) are noncancerous growths within the nose or sinuses. Symptoms include trouble breathing through the nose, loss of smell, decreased taste, post nasal drip, and a runny nose. The growths are sac-like, movable, and nontender, t .... Allele distribution Sources * References {{HLA-A serotypes 7 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
