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Journal of Political Ecology:
Case Studies in History and Society
VOLUME 6 (1999)
Adaptation to Malaria: The Interaction of Biology and Culture. Edited by Lawrence S. Greene and Maria Enrica Danubio. xiv + 490 pp. New York: Gordon and Breach. 1997.
Review by Kevin M. Kelly, University of Iowa College of Public Health.
Malaria currently affects over 400 million people worldwide. Seeing that this number continues to grow, Greene and Danubio (p. 2) rhetorically ask whether "future health endeavors might profit from an understanding of the way in which human populations have adapted to malaria in the past--both biologically and culturally." This volume highlights their insightful statement.
At the outset, potential readers should be warned that despite the title, this informative, interdisciplinary volume is not a treatise on the broad scope of human adaptation to malaria. Rather, an impressive list of contributors examine glucose-6-phosphate dehyrogenase [G6PD] deficiency, its physiology, genetic variants, distribution and interaction with cultural adaptations to malaria.
16 well-referenced contributions are arranged under three section headings
[Table of Contents]. The first section explores the molecular genetics,
biochemistry, epidemiology and clinical sequallae of G6PD-deficiency.
In Chapter 1, by Gaetani and Ferrans, describes the basic biochemistry
of oxidative stress and G6PD-deficiency, the G6PD alleles, their properties
and roles in producing the deficiency. A well-referenced table classifying
the numerous G6PD variants accompanies the discussion and is particularly
useful. In another excellent chapter, Turrini et al. (Chapter 2)
detail the biochemistry of favism, the hemolytic crisis following consumption
of fava beans. The authors lay the biological basis for a co-evolved
dietary adaptation as well as presenting evidence for their own novel
hypothesis that auto-antibodies facilitate the antimalarial effects of
G6PD-deficiency. The first section concludes with two chapters on G6PD
morbidity. The first of these (Chapter 3), an epidemiological discussion
of "favism, neonatal jaundice, and infection-induced acute hemolytic
anemia," is instructive although somewhat not in keeping with the
focus of the volume. In the final chapter of this section, a case-control
study of uncomplicated and severe malaria in Africa, Ruwende et al. refocus
our attention on the selective advantage to malaria conferred by G6PD
deficiency providing us with odds ratios to estimate the relative risks
section is a somewhat uneven set of chapters that discuss the possible
mechanisms of antimalarial protection in G6PD-deficient individuals as
well as the related and more general subject of dietary and medicinal
oxidant induced protection. The three initial chapters of the section
discuss the damaging effects of reactive oxygen species on the red blood
cells and malaria parasites. In Chapter 5, Scott and Eaton hypothesize
that G6PD deficiency provides protection against malaria by the premature
aging and consequently to the destruction of host red blood cells. This
mechanism is somewhat analogous to the differential destruction of sickled
red blood cells. However, in this model the accumulation of loose heme
and iron in infected cells of G6PD deficient individuals leads to oxidant
stress and aging. Har-El and Chevion (Chapter 6) follow with a detailed
description and discussion the chemistry of iron in reference to oxidative
stress in infected red blood cell. Completing the triad, Golenser (Chapter
7) describes how oxidative stress can lead to damage to the host cell
as well as to the parasite. The final chapters of Section II explore the
use, mechanisms and co-evolved human use of oxidant-inducing plants as
protection against malaria. Etkins (Chapter 8) excellently referenced
and noted summary of indigenous pharmacopeias shown to have antimalarial
(oxidative) action begins the next triad of the section. Etkin argues
that the use of medicinal and dietary use of oxidant-containing plants
is the cultural analog to G6PD-deficiency, producing the same effect but
at a lower cost. In Chapter 9, Jackson attempts to provide a conceptual
framework for understanding the evolution of human-plant-parasite interactions.
Closing the section, Greene (Chapter 10) addresses the roles of various
nutrients with reference to the notion that dietary patterns are a co-evolved
mechanism for potentiating the antimalarial effects of G6PD-deficiency.
section includes six essays that variously discuss historic and genetic
data related to the distribution of G6PD-deficient alleles in southern
Italy and Sardinia. In Chapter 11, Tognotti discusses the spread of malaria
in Sardina. In one of the more ambitious chapters, Tagarelli et al. (Chapter
12) explore historic, orographic and genetic factors related to distribution
of malaria G6PD in Calabria. In Chapter 13, Astolfi et al. (Chapter
13) suggest that the G6PD and thallassemia balanced polymorphisms have
been maintained by differential fertility and survival. Sanna et
al. (Chapter 14) discuss the origin and epidemiology of malaria in Sardinia
as well as malarias distribution in relation to G6PD deficiency.
Danubio (Chapter 15) describes "methodological aspects of the biodemographic
approach" with a brief discussion of how this approach might be applied
to understanding the distribution to G6PD alleles. In Chapter 16 Gloria-Bottini
et al. explore the sequence of genetic adaptations to malaria, focusing
in particular on the interaction between G6PD-deficiency and thalassemia.
chapter (Chapter 17) is an attempt by the editors to place each chapter
and section in perspective. While I greatly appreciated their efforts,
I could not help but wonder if the readers would have been better served
by editors' comments preceding each of the three sections. In addition,
a chapter more generally discussing the pathogenesis of malaria as well
as one or two chapters on G6PD in Africa would have been very instructive.
Finally, given the varied backgrounds of the contributors to and the potential
audience of this volume, abstracts preceding each chapter as well as a
glossary at the end of the volume would have been helpful.
has a recurring theme that human adaptation to malaria is biological and
cultural. That theme arises from the often-cited evidence that diets that
include oxidant-containing plant foods as well as therapeutic regimens
that lower erythrocyte redox capacity, maximize the antimalarial protection
of red blood cells in general and G6PD deficient cells in particular.
While that point is well made, I have some concerns that that theme, like
the title, does not generalize to other human adaptations to malaria (e.g.,
sickle-cell trait, the thallasemias). Indeed, the volumes focus
on diet might leave some reader believing that oxidative stress is the
only mechanism of resistance to malaria. While this might seem a minor
point, it evinces the broader scope of human adaptation. In fact, in reading
the volume, I sense two intertwined stories being told. One is the role
of G6PD in the context of cultural and biological adaptations to malaria,
the other the story of favism and acute hemoltyic anemia in the context
of the genetic legacy of a biocultural adaptation to malaria. Here again
these intertwined stories recall the editors concerns that public
health concerns might be better addressed understanding the biological
and cultural bases of human adaptation.
Overall, Greene and Danubio have produced an informative volume that can be recommended to anyone interested human adaptations to malaria or disease in general. Researchers, students, biochemists, geneticists, malariologists, and anthropologists will benefit from the references and tables as well as from the thoughtful effort to integrate biology and culture. For, as this volume demonstrates, understanding the human experience and struggle with malaria truly requires an understanding of the interaction of biology and culture.