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Negative epistasis between ?+ thalassaemia and sickle cell trait can explain interpopulation variation in South Asia.

ABSTRACT: Recent studies in Kenya and Ghana have shown that individuals who inherit two malaria-protective genetic disorders of haemoglobin-?(+) thalassaemia and sickle cell trait-experience a much lower level of malaria protection than those who inherit sickle cell trait alone. We have previously demonstrated that this can limit the frequency of ?(+) thalassaemia in a population in which sickle cell is present, which may account for the frequency of ?(+) thalassaemia in sub-Saharan Africa not exceeding 50%. Here we consider the relationship between ?(+) thalassaemia and sickle cell in South Asian populations, and show that very high levels of ?(+) thalassaemia combined with varying levels of malaria selection can explain why sickle cell has penetrated certain South Asian populations but not others.

SUBMITTER: Penman BS

PROVIDER: S-EPMC3263337 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature

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Negative epistasis between α+ thalassaemia and sickle cell trait can explain interpopulation variation in South Asia.

Penman Bridget S BS Habib Saman S Kanchan Kanika K Gupta Sunetra S

Evolution; international journal of organic evolution 20110811 12

Recent studies in Kenya and Ghana have shown that individuals who inherit two malaria-protective genetic disorders of haemoglobin-α(+) thalassaemia and sickle cell trait-experience a much lower level of malaria protection than those who inherit sickle cell trait alone. We have previously demonstrated that this can limit the frequency of α(+) thalassaemia in a population in which sickle cell is present, which may account for the frequency of α(+) thalassaemia in sub-Saharan Africa not exceeding 5 ...[more]

PMID: 22133230

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Negative epistasis between ?+ thalassaemia and sickle cell trait can explain interpopulation variation in South Asia.

Publications

Negative epistasis between α+ thalassaemia and sickle cell trait can explain interpopulation variation in South Asia.

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