ALFRED: allele frequency database

The ALlele FREquency Database
ALFRED is a resource of gene frequency data on human populations
supported by the U. S. National Science Foundation.

ALFRED detailed record information

Polymorphism Information

Name	ALFRED UID	Locus Name	Locus Symbol
HLA-DQA1	SI000578U	Major histocompatibility complex	MHC

Synonyms:
Frequency Display Formats:

Estimated Heterozygosity:

Frequency Download:

External Resources: dbMHC database Record
References: See References
Polymorphism Description: The HLA-DQA1 gene, which encodes for the alpha chain includes six allele groups or lineages DQA1*01, DQA1*02, DQA1*03, DQA1*04, DQA1*05, and DQA1*06. The gene consists of five exons and four introns.There are 27 alleles presently known.

Majority of the data in ALFRED for this site are from forensic studies and are typed using the kits- Amplitype� HLA DQA1 Amplification and Typing kit and Amplitype PM+DQA1 Amplification and Typing kit which uses PCR combined with reverse dot blot technology.

The HLADQA1 alleles typed by these methods are designated 1.1,1.2,1.3,2,3,4.1,4.2,4.3 all of which are located within the second exon of the HLA-DQA1 gene. The molecular differences among these alleles are detailed in Horn et al (1988).Six alleles-1.1,1.2,1.3,2,3 and 4 are distinguished by the former kit.The latter kit enables the allele 4 to be subtyped into either 4.1 or a 4.2/4.3 allele.

The corresponding allele names and symbols from HLA nomenclature committee(ref :Bodmer et al, 1998) are given in the allele table.

Alleles:

Allele Name	Allele Symbol	Description
4	4	composed of alleles 4.1,4.2 and 4.3 undifferentiated
4.2/4.3	4.2/4.3	composed of alleles 4.2 and 4.3 undifferentiated
DQA1*0101	DQA1*0101	previously known as 1.1
DQA1*0102	DQA1*0102	previously known as 1.2
DQA1*0103	DQA1*0103	previously known as 1.3
DQA1*0201	DQA1*0201	previously known as 2
DQA1*0301	DQA1*0301	previously known as 3
DQA1*0401	DQA1*0401	previously known as 4.2
DQA1*0501	DQA1*0501	previously known as 4.1
DQA1*0601	DQA1*0601	previously known as 4.3

References:
- Bodmer JG, Marsh SG, Albert ED, Bodmer WF, Bontrop RE, Dupont B, Erlich HA, Hansen JA, Mach B, Mayr WR, Parham P, Petersdorf EW, Sasazuki T, Schreuder GM, Strominger JL, Svejgaard A, Terasaki PI. "Nomenclature for factors of the HLA system, 1998". Tissue Antigens 53:407-46.. (1999) Online citation.

- Budowle B, Lindsey JA, DeCou JA, Koons BW, Giusti AM, Comey CT. "Validation and population studies of the loci LDLR, GYPA, HBGG, D7S8, and Gc (PM loci), and HLA-DQ alpha using a multiplex amplification and typing procedure". J Forensic Sci. 40:45-54.. (1995) Online citation.

- Gyllensten UB, Erlich HA. "Generation of single-stranded DNA by the polymerase chain reaction and its application to direct sequencing of the HLA-DQA locus". Proc Natl Acad Sci U S A. 85:7652-6.. (1988) Online citation.

- Horn GT, Bugawan TL, Long CM, Erlich HA. "Allelic sequence variation of the HLA-DQ loci: relationship to serology and to insulin-dependent diabetes susceptibility". Proc Natl Acad Sci U S A 85:6012-6. (1988) Online citation.

- Walsh PS, Erlich HA, Higuchi R. "Preferential PCR amplification of alleles: mechanisms and solutions. ". PCR Methods Appl. 1:241-50. (1992) Online citation.

© 2012 Kenneth K Kidd, Yale University. All rights reserved. The full Copyright Notification is also available.
Originally prototyped by Michael Osier with the aid of Kei Cheung
Upgrades and maintenance since 2002 by Haseena Rajeevan