HLA-DR7 (DR7) is a HLA- DR serotype that recognizes the DRB1*0701 to *0705 gene products.

Serology

The serological reaction of DR7 is excellent for *0701. The serology of *0703 to *0705 to *0709, and *0711 to *0714 serotypes is unknown. DRB1*0710N is a

null allele A null allele is a nonfunctional allele (a variant of a gene) caused by a genetic mutation. Such mutations can cause a complete lack of production of the associated gene product or a product that does not function properly; in either case, the all ...

. DRB1*0702 nomenclature has been deleted.

Disease associations

By serotype

DR7 is positively associated with

psoriasis vulgaris Psoriasis is a long-lasting, noncontagious autoimmune disease characterized by patches of abnormal skin. These areas are red, pink, or purple, dry, itchy, and scaly. Psoriasis varies in severity from small localized patches to complete body ...

By Allele group

DRB1*07 is linked to ''T. cruzi'' infection with

cardiomyopathy Cardiomyopathy is a group of primary diseases of the heart muscle. Early on there may be few or no symptoms. As the disease worsens, shortness of breath, feeling tired, and swelling of the legs may occur, due to the onset of heart failure. A ...

(also called Chaga's cardiomyopathy).

By extended haplotype

DR7:DQA1*0201:DQB1*0202 is associated with

Graves' disease Graves' disease, also known as toxic diffuse goiter or Basedow's disease, is an autoimmune disease that affects the thyroid. It frequently results in and is the most common cause of hyperthyroidism. It also often results in an enlarged thyro ...

. DR7- DQ2/ DR5- DQ7 phenotype (transhaplotype encoded isoform DQα⁵β²) is the primary risk DQ isoform in

celiac disease Coeliac disease (British English) or celiac disease (American English) is a long-term autoimmune disorder, primarily affecting the small intestine. Patients develop intolerance to gluten, which is present in foods such as wheat, rye, spel ...

. DR7-DQ2/DR5-DQ7 (/ DR11-DQ7 or / DR12-DQ7) is a clarifying identifier for the at risk transhaplotype. DR53-DR7 may be associated with sclerosis/lupus associated

anti-apolipoprotein antibodies In autoimmune disease, anti-apolipoprotein H (AAHA) antibodies, also called anti-β2 glycoprotein I antibodies, comprise a subset of anti-cardiolipin antibodies and lupus anticoagulant. These antibodies are involved in sclerosis and are strongly a ...

Genetic linkage

HLA-DR7 is genetically linked

HLA-DR53 HLA-DR53 is an HLA-DR serotype that recognizes gene products of HLA-DRB4 locus. There are 13 alleles at this locus that encode 7 proteins. DRB3, DRB4, and DRB5 are minor DR beta encoding loci, they have been recognized as having distinct evolutio ...

, and is linked to DQ2

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 Cell (biology), cells are classified together based on their shared reactivity ...

s. There are a few interesting genetics with DR7. The A29-Cw16-B44-DR7-DQ2

haplotype A haplotype (haploid genotype) is a group of alleles in an organism that are inherited together from a single parent. Many organisms contain genetic material (DNA) which is inherited from two parents. Normally these organisms have their DNA orga ...

is in strong linkage disequilibrium particularly in Northwestern Europe. The highest frequencies tend to be coastal countries along the Atlantic. The Cw16 allele is undoubtedly derived from Western Africa the diversity and frequency of Cw16 declines away from the along the

Greenwich Greenwich ( , , ) is an List of areas of London, area in south-east London, England, within the Ceremonial counties of England, ceremonial county of Greater London, east-south-east of Charing Cross. Greenwich is notable for its maritime hi ...

longitudinal line. The level of linkage disequilibration about Cw16 postulates a recent arrival from Africa, and indicates a substantial contribution as far north as

Ireland Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...

. The A33-Cw7-B44-DR7 offers the same scenario. This haplotype is found in Korea but not Japan, in fact Japan is an

antinode A node is a point along a standing wave where the wave has minimum amplitude. For instance, in a vibrating guitar string, the ends of the string are nodes. By changing the position of the end node through frets, the guitarist changes the effec ...

of DR7. The most frequent A-B-DR-DQ haplotypes in Korea are found at ~3/4 the Korean frequencies in Japan, except A33-Cw7-B44-DR7-DQ2, which indicates that DR7 likely spread into

Korea Korea is a peninsular region in East Asia consisting of the Korean Peninsula, Jeju Island, and smaller islands. Since the end of World War II in 1945, it has been politically Division of Korea, divided at or near the 38th parallel north, 3 ...

after the

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

's Yayoi migration when most of the Korean contribution occurred. Similarities with Mongol genes suggest that Central and East- Central Asian are the likely source, confirmed by the fact the haplotype is found in

Pakistan Pakistan, officially the Islamic Republic of Pakistan, is a country in South Asia. It is the List of countries and dependencies by population, fifth-most populous country, with a population of over 241.5 million, having the Islam by country# ...

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

and

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

. There is the possibility that this haplotype is a recent (

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

) arrival from Africa or the Middle East to Central Asia as this best explains the alleles within the haplotype. The A19 (A29, A30, A31, A32, A33, A74) serotypes are very much enriched in sub-saharan and Western Africa, including Iberia, and disequilibrated components of DR7 show a tendency to be linked to A19 serotypes.

References

{{DEFAULTSORT:Hla-Dr7 7