Abstract:
:Genes comprising the major histocompatibility complex (MHC) play a central role in governing the immune response of vertebrates. A great deal of information has been revealed on the molecular biology and physiology of these loci, but three features-the high polymorphism, tight linkage among the loci, and the nonrandom association of alleles-make the system of particular interest from the perspective of population genetics. Information on the dynamic evolutionary forces that have acted on a locus can be inferred from the number and distribution of alleles that it carries. Ten loci from the HLA region of the human MHC, each sampled from several different populations, have been examined for departures from the expected value of homozygosity under the condition of selective neutrality. The homozygosities of five class I and II loci that code for membrane glycoproteins, HLA-A, -B, -C, -DR, and -DQ, and of glyoxylase I (GLO) were significantly less than the neutrality expectations. This suggests the presence of some form of balancing selection. In spite of being closely linked, in fact, located between the class I and class II histocompatibility loci, the homozygosities of the four class III or complement loci C2, Bf, C4A, and C4B, which are detected by electrophoresis, were indistinguishable from, or exceeded, that expected under neutrality. Although this conforms to the suggestion that, in general, electrophoretic variants are neutral, because of the tight linkage to loci demonstrating a history of selection, it is possible that the mechanism for generating variation in the class III loci may be different from that of the class I and class II loci.
journal_name
Am J Hum Genetjournal_title
American journal of human geneticsauthors
Klitz W,Thomson G,Baur MPsubject
Has Abstractpub_date
1986-09-01 00:00:00pages
340-9issue
3eissn
0002-9297issn
1537-6605journal_volume
39pub_type
杂志文章abstract::Waardenburg syndrome type 4 (WS4), also called Shah-Waardenburg syndrome, is a rare neurocristopathy that results from the absence of melanocytes and intrinsic ganglion cells of the terminal hindgut. WS4 is inherited as an autosomal recessive trait attributable to EDN3 or EDNRB mutations. It is inherited as an autosom...
journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/302895
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journal_title:American journal of human genetics
pub_type: 杂志文章
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journal_title:American journal of human genetics
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/318198
更新日期:2001-02-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/346090
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/302243
更新日期:1999-02-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/324565
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/377156
更新日期:2003-08-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1979-07-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1978-01-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/345466
更新日期:2003-01-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1994-11-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1997-03-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1016/j.ajhg.2012.02.012
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journal_title:American journal of human genetics
pub_type: 杂志文章
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更新日期:2010-01-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1016/j.ajhg.2009.08.002
更新日期:2009-09-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1016/j.ajhg.2010.03.011
更新日期:2010-05-14 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1996-10-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1988-07-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1992-09-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/302402
更新日期:1999-06-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1993-12-01 00:00:00
abstract::Recent studies have suggested that a significant fraction of the human genome is contained in blocks of strong linkage disequilibrium, ranging from ~5 to >100 kb in length, and that within these blocks a few common haplotypes may account for >90% of the observed haplotypes. Furthermore, previous studies have suggested...
journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/382227
更新日期:2004-04-01 00:00:00
abstract::Criteria and rules are derived for the most statistically efficient sampling of relatives of affected probands under a simple class of standard genetic models. Results show that the optimal relative type depends on the alternative hypotheses of particular interest. Thus, there is no uniformly optimal strategy, but the...
journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1981-11-01 00:00:00
abstract::The frequencies of different HLA-A and -B alleles in 77 Australian patients with hemochromatosis have been compared with frequencies of HLA alleles not associated with hemochromatosis in 63 of their heterozygous relatives and with published population frequencies. As for all other populations reported, an association ...
journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
更新日期:1989-07-01 00:00:00
abstract::Supernumerary marker chromosomes (SMCs) are common, but their molecular content and mechanism of origin are often not precisely characterized. We analyzed all centromere regions to identify the junction between the unique chromosome arm and the pericentromeric repeats. A molecular-ruler clone panel for each chromosome...
journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1016/j.ajhg.2007.10.013
更新日期:2008-02-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:10.1086/324024
更新日期:2001-11-01 00:00:00
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
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journal_title:American journal of human genetics
pub_type: 杂志文章
doi:
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