Prior research into Major Histocompatibility Complex (MHC) has shown that this complex restricts antigen presentation. Using this past research as a basis three scientists have used a general model to determine if allele-specific dominance applies to the heterozygous and homozygous allele at the Major Histocompatibility Complex. An allele-specific dominance is described as a ‘more vigorous immune responses to a pathogen by a heterozygote as compared to homozygotes for the same alleles’. Through the general model, instead of verifying they found a phenomenon that they have called “population heterozygote advantage"
What they discovered was that people who were heterozygous at the MHC had a better immune response then people who were homozygous. This meant even if biological and mechanical factors were similar in two different populations but the amount of alleles were different then one population would have a better immune response that the other.
What they discovered was that people who were heterozygous at the MHC had a better immune response then people who were homozygous. This meant even if biological and mechanical factors were similar in two different populations but the amount of alleles were different then one population would have a better immune response that the other.
There was no single allele that was seen to be more dominant than all the others. In the general model they reduced the alleles to two which were S and R. As each allele had a different impact on the immune responses with some having a stronger response than others and others having no effect at all further research is needed in this area.
Research in this area can be particularly useful in the area of vaccine design as well as population and epidemiological studies looking at populations having different immune responses.
Allele-specific overdominace was not concluded in this experiment as each allele has a different effect to another. Rather it was seen that homozygote's at the MHC locus has a worse immune response than those who were heterozygous for the same locus.
By Hannah Jensen-Fielding (42018498)
References:
Antia R, Bergstrom C, Lipsitch M 2002, ‘Effect of human leukocyte antigen heterozygosity on infectious disease outcome: The need for allele-specific measures’, Biomed Central, vol 4 , viewed 19 April 2009,
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