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Craniofacial Morphogenesis and Dysmorphogenesis. Edited by Katherine W.L. Vig and Alphonse R. Burdie. Ann Arbor MI Center for Human Growth and Development. 1988. x + 221 pp. figures tables references. $30

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essentially ignored. Only in Van Esterik’s
chapter is a biological basis for a cultural
phenomenon proposed. While the biological
component is assumed in several chapters
(for example, in discussions of depression),
it is infrequently woven into the exploration
of the experience of illness. While the editor
claims this book to be “holistic” in approach,
a n important element in the discussion h a s
been laid aside. Certain chapters suffer as
well from a degree of Western ethnocentricity, assuming t h a t a Western medical mode
of disease/illness can serve as the basis for
discussion of disease/illness in other societies. For example, symptoms that are presented by suffers of neruios are said to make
the condition one that “resembles depression.” This approach does not admit that
“depression” is a culturally constructed
category, based on a particular allocation of
symptoms. A similar error is made in discussions of “stress.” “Stress” is a Western
notion, which is defined and interpreted differently even among participants in Western culture, one t h a t may or may not have
equivalents in other societies. A serious
examination of causal factors and the effects
and expression of stress should not be begun
without stating the culturally biased basis
for the discussion.
Overall, however, the book would be a fine
choice for a n introductory or upper level
course in medical anthropology, medical
sociology, or women’s studies, provided the
book was used in conjunction with a text
t h a t more fully explores important theoretical issues within these fields. Each author
h a s incorporated a brief but useful summary
of the theoretical position or positions t h a t
provided the foundation for her research,
without ignoring the pragmatic implications
for national health care policies. The book
concludes with a n extensive bibliography,
which provides a useful basis for further
Vig and Alphonse R. Burdie. Ann Arbor,
MI: Center for Human Growth and Development. 1988. x
221 pp., figures,
tables, references. $30.00 (cloth).
sion, the question t h a t remains to be largely
answered is how much of the variation t h a t
we consider to be “normal” is in fact a
consequence of morphologic, enzymatic,
genetic, and/or chromosomal abnormalities? As noted by the editors,
The Symposium Series of the Center for
Human Growth a n d Development h a s a
well-deserved reputation for producing highquality, well-thought-out volumes holding
important clinical implications. Craniofacia1 Morphogenesis and Dysmorphogenesis
continues that tradition by providing a
fresh perspective of craniofacial variation.
It should be read by anyone interested in
craniofacial biology.
As implied, the volume focuses on dysmorphology, defined as “normal development gone awry,” and syndromology. It has
been estimated that approximately 3-5% of
human newborns have congenital anomalies requiring medical attention. That figure
doubles with increasing age, as the functional consequences of malformations become apparent. Since these proportions
merely identify extreme phenotypic expres-
Department of Human Resources
State of Oregon
Salem, Oregon
The challenge confronting the clinician is
not the recognition of the fully expressed
syndromic pattern but of the phenotype variance which places a patient in that poorly
defined area commonly referred to as “an
extreme of normal variation.”
Hall sets the tone of the volume in the first
chapter, which reviews embryonic induction, neural crest regulation, differentiation,
migration, and localization. Physical anthropologists should be particularly interested
in the effects of excess vitamin A, which
slows migration of the neural crest cells,
leading to formation of craniofacial structures in ectopic positions. Of functional significance, avian neural crest-mesoderm
boundaries clearly distinguish skeletal elements deriving from mesoderm and neural
crest. Mesenchymal condensations are
emphasized since their size and time of
appearance influence differentiation and,
consequently, dysmorphogenesis. Hall’s
summary is clear, concise, and provocative.
It should not be overlooked.
The remaining chapters are equally as
interesting and insightful. I n chapter 2
Carlson distinguishes between morphogenesis and pattern formation. He interprets the
former a s the blueprint and the latter as the
growth process itself. The later pattern formatmionoccurs, the less impact it has on the
developing embryo. Appropriately, this short
chapter raises more questions than it answers. The implications of developmental
fields for craniofacial biology are briefly
reviewed in chapter 11.Critical time periods
of temporal mandibular joint (TMJ) development (7-11 weeks intrauterine weeks),
developmental associations between fields
(including skeletal and muscular), and differential growth of fields (ramal field increases a t a greater rate than the body field)
are the primary focal points of discussion.
Two of the chapters are devoted to environmental factors influencing craniofacial
morphogenesis. Pratt discusses the effects
of glucocorticoids, dioxin, and retinoids on
craniofacial development in chapter 3. Glucocorticoids apparently serve as metabolic
regulators whose actions are mediated
through intracellular protein receptors. They
can inhibit the formation of the secondary
palate. Interestingly, susceptibility appears
to be species specific. Dioxin induces cleft
palate through abnormal enzymatic activity, which in turn alters epidermal cell differentiation. Excessive vitamin A causes a
variety of malformations. Although facial
anomalies appear to be the most outstanding, all the major systems may be affected.
Chapter 4,by Brinkley, focuses on the role
of extracellular matrices in palate formation
and shelf remodelling. Emphasis is placed
on the possible effects of environmental
agents on the synthesis of glycosaminoglycans, glycoproteins, and collagen.
Three of the chapters introduce new techniques and methodologies for studying craniofacial development. Diewert and Lozanoff describe primary palate formation using
finite elements. The technique, which was
developed to understand better how form
changes in response to stress and strain, is
reference frame invariant. As such, it
appears particularly well suited for describing relative shape differences associated
with dysmorphology. I n chapter 9, Marsh
and Vannier bring readers up to date on
techniques used for three-dimensional surface reformation from CT scans. The technology offers astounding possibilities to see
structures a s never before possible; applications are limited only by the imagination, or
lack thereof. It h a s been a long-standing
interest of morphologists to describe and
better understand curves rather than isolated points. I n chapter 10, Bookstein and
Cutting review techniques for studying form
as it curves in-between landmarks. Twodimensional techniques t h a t go around the
outline and techniques that go across the
outline are briefly described. They introduce
the possibility of modelling the form of
curves in three dimensions, which will certainly move analysis to a new, more encompassing, level.
Two chapters have been devoted to surgery. In chapter 8 Kremenak and coworkers
discuss possible sex differences in growth
responses to cleft palate surgery. Summarizing data derived from experiments involving beagles, they find that sex differences
influence maxillary growth after palate
surgery, which might be partially explained
by dimorphic postsurgical growth potential.
McCarthy provides a n excellent, matter of
fact description of surgical treatments of
craniofacial dysmorphology in chapter 13.
These procedures are now commonly performed and can produce radical improvements for patients with deformities. A great
deal of research is presently being conducted to understand better the variation
associated with surgical treatment. The
tendency toward treating younger individuals parallels our increased understanding of
normal and abnormal growth patterns without treatment.
In chapter 12, Vig gives a superb account
of how orthodontists should relate to craniofacial dysmorphology and, thereby, provides
important insights into how physical anthropologists might best approach this area of
study. The primary syndromes are summarized, and their treatments are reviewed.
Collaboration with basic scientists is emphasized to find controlling mechanisms. Her
review is “must” reading for anyone interested in abnormal craniofacial growth and
t h e orthodontic/surgical management
thereof. Poswillo’s chapter focuses on the
developmental relationship between the ear
and the mandible and on how this association might be used better to understand
malformations and deformations. He raises
the question of whether or not we can use
the external and/or middle ear as potential
markers of impending mandibular growth
Building upon his previous work, Babler
clearly describes the effects of multiple
suture closure on craniofacial growth in
chapter 6. He shows that premature closure
of the coronal, sagittal, and interfrontal
sutures produces craniofacial deformities;
compensatory growth occurs a t the parietotemporal suture. Growth a t the anterior
lambdoidal suture actually decreases! The
cranial base, and in turn the midfacial and
mandibular relationships, are also significantly altered.
Ackerman provides a n overview of morphogenesis and dysmorphogenesis from a
clinical perspective in the concluding chap-
ter. His personal recollections of Professor
Krogman should be of particular interest to
physical anthropologists. The development
of cephalometrics, which is probably the
most widely used and important tool for
understanding craniofacial growth, was
greatly influenced by the orthodontists’
early fascination with physical anthropology. Concentration has more recently shifted
to the molecular level. Ackerman suggests
that such a focus is too narrow; he calls upon
craniofacial biologists to bridge the gap
between the molecular and clinical perspectives. Physical anthropologists are extremely
well suited to assume such a role.
Orthodontic Department
Baylor College o f Dentistry
Dallas, Texas
OF SEX DIFFERENTIATION.ies of the Y chromosome. Susumu Ohno’s
Edited by Florence P. Haseltine, Michael chapter “Antiquity of the Genetic MechaE. McClure, a n d Ellen H. Goldberg. New nism of Sex Determination . . .” provides a
York: Plenum Publishing Corporation. readable and general evolutionary perspec1987. viii 176 pp., figures, tables, refer- tive on the issues at hand. For the most part,
however, the chapters are quite technical.
ences, index. $45.00 (cloth).
The chapters dealing with the H-Y antigen
are not easily absorbed by readers without
some background in immunology. The chapGenetic Markers of Sex Differentiation is ter by Ellen Goldberg and Brian Reilly
a collection of papers presented at a n NIH stands out among these as being a lucid
workshop on the mechanisms of sex deter- presentation of complex material. Peter
mination. The list of contributors is impres- Goodfellow discusses the search for genes
sive, and the chapters are organized well on the Y chromosome and, for physical
and written clearly. It is particularly remark- anthropologists, this might be a chapter of
able that the workshop was held in late some particular interest.
As a whole, the volume assumes some
1986 and the book copyright is 1987.
Florence Haseltine wrote a n excellent Intro- basic appreciation of immunology, cytogeduction to the volume. She discusses the netics, and molecular biology. Physical
major issues involved in the study of sex anthropologists may find the majority of
determination and then encapsulates each chapters rather arduous, although the topic
chapter in a concise, cohesive fashion. For itself is certainly one of great interest to stuthe general reader, this Introduction is dents of human evolution. Extensive referprobably the most critical section i n the ences are provided throughout the volume,
volume. I referred back to it often for the and the interested reader could easily use
perspective it lends to the subsequent these to fill in the gaps between the technical aspects of any particular report and the
Topics covered i n the 13 chapters include broad evolutionary questions about sex
1)the H-Y antigen and its role in sexual dif- determination t h a t this volume addresses.
ferentiation, 2) evolutionary perspectives to
Department of Neurology
be gained from the study of sex determinaOregon Health Science University
tion in animals other t h a n humans (i.e., repPortland, Oregon
tiles and marsupials), a n d 3) molecular stud-
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development, vig, burdie, figuren, growth, 1988, references, katherine, alphonse, arbors, human, dysmorphogenesis, craniofacial, ann, edited, tablet, center, morphogenesis, 221
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