Hardy-Weinberg principle: Difference between revisions

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(New page: In genetics, the '''Hardy–Weinberg principle''' states that gene frequency remains constant across generations (no genetic drift) unless a force causes phenomena such as [[gene f...)
 
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In genetics, the '''Hardy–Weinberg principle''' states that [[gene frequency]] remains constant across generations (no [[genetic drift]]) unless a force causes phenomena such as [[gene flow]].
In [[genetics]], the '''Hardy–Weinberg principle''' states that [[gene frequency]] remains constant across generations (no [[genetic drift]]) unless a force causes phenomena such as [[gene flow]].


In an example of two alleles, 'A' and 'a', random frequency is based on the binomial expansion
In an example of two alleles, 'A' and 'a', random frequency is based on the binomial expansion
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Testing for Hardy–Weinberg equilibrium is studies of associations between [[genetic polymorphism]]s and diseases is controversial.<ref name="pmid17044866">{{cite journal| author=Zou GY, Donner A| title=The merits of testing Hardy-Weinberg equilibrium in the analysis of unmatched case-control data: a cautionary note. | journal=Ann Hum Genet | year= 2006 | volume= 70 | issue= Pt 6 | pages= 923-33 | pmid=17044866  
Testing for Hardy–Weinberg equilibrium is studies of associations between [[genetic polymorphism]]s and diseases is controversial.<ref name="pmid17044866">{{cite journal| author=Zou GY, Donner A| title=The merits of testing Hardy-Weinberg equilibrium in the analysis of unmatched case-control data: a cautionary note. | journal=Ann Hum Genet | year= 2006 | volume= 70 | issue= Pt 6 | pages= 923-33 | pmid=17044866  
| url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=clinical.uthscsa.edu/cite&email=badgett@uthscdsa.edu&retmode=ref&cmd=prlinks&id=17044866 | doi=10.1111/j.1469-1809.2006.00267.x }} <!--Formatted by http://sumsearch.uthscsa.edu/cite/--></ref><ref name="pmid16410351">{{cite journal| author=Trikalinos TA, Salanti G, Khoury MJ, Ioannidis JP| title=Impact of violations and deviations in Hardy-Weinberg equilibrium on postulated gene-disease associations. | journal=Am J Epidemiol | year= 2006 | volume= 163 | issue= 4 | pages= 300-9 | pmid=16410351  
| url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=clinical.uthscsa.edu/cite&email=badgett@uthscdsa.edu&retmode=ref&cmd=prlinks&id=17044866 | doi=10.1111/j.1469-1809.2006.00267.x }} <!--Formatted by http://sumsearch.uthscsa.edu/cite/--></ref><ref name="pmid16410351">{{cite journal| author=Trikalinos TA, Salanti G, Khoury MJ, Ioannidis JP| title=Impact of violations and deviations in Hardy-Weinberg equilibrium on postulated gene-disease associations. | journal=Am J Epidemiol | year= 2006 | volume= 163 | issue= 4 | pages= 300-9 | pmid=16410351  
| url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=clinical.uthscsa.edu/cite&email=badgett@uthscdsa.edu&retmode=ref&cmd=prlinks&id=16410351 | doi=10.1093/aje/kwj046 }} <!--Formatted by http://sumsearch.uthscsa.edu/cite/--></ref> Studies having violations of equilibrium may have less stable results and may tend to have more positive results.<ref name="pmid16410351">{{cite journal| author=Trikalinos TA, Salanti G, Khoury MJ, Ioannidis JP| title=Impact of violations and deviations in Hardy-Weinberg equilibrium on postulated gene-disease associations. | journal=Am J Epidemiol | year= 2006 | volume= 163 | issue= 4 | pages= 300-9 | pmid=16410351
| url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=clinical.uthscsa.edu/cite&email=badgett@uthscdsa.edu&retmode=ref&cmd=prlinks&id=16410351 | doi=10.1093/aje/kwj046 }} <!--Formatted by http://sumsearch.uthscsa.edu/cite/--></ref>
| url=http://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=clinical.uthscsa.edu/cite&email=badgett@uthscdsa.edu&retmode=ref&cmd=prlinks&id=16410351 | doi=10.1093/aje/kwj046 }} <!--Formatted by http://sumsearch.uthscsa.edu/cite/--></ref>


==References==
==References==
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Revision as of 12:40, 10 December 2009

In genetics, the Hardy–Weinberg principle states that gene frequency remains constant across generations (no genetic drift) unless a force causes phenomena such as gene flow.

In an example of two alleles, 'A' and 'a', random frequency is based on the binomial expansion

Thus the following distributions are examples of equilibrium:

  • AA is 100%; Aa and aa are both 0%
  • aa is 100%; Aa and AA are both 0%
  • Aa is 50%; AA and aa are both 25%
  • Aa is 4/9; AA is 4/9 and aa is 1/9
  • Aa is 4/9; AA is 1/9 and aa is 4/9

Testing for Hardy–Weinberg equilibrium is studies of associations between genetic polymorphisms and diseases is controversial.[1][2] Studies having violations of equilibrium may have less stable results and may tend to have more positive results.[2]

References