Arguably, they can be considered a phenotype, as they can reflect the influence of metabolism and environment on an existing body component alternatively they can reflect a heritable influence and be considered part of the genotype. Histone marks and epigenetic factors modifying the DNA sequence exist at the boundary of genotype and phenotype. The definition excludes the primary morphology (i.e., DNA sequence structure) of the genotype as being part of the phenotype. The word phenotype is derived from the Greek ϕ (phaino) meaning “shining” or “showing” and ( tupos) meaning “type.” The phenotype encompasses all attributes of an individual, both at a cell or tissue level (e.g., physiology) and at the level of the individual (e.g., behavior or cognition). DEFINITIONS Phenotype DefinitionĪll morphologic and functional attributes of an individual, or of the organs, tissues, or cells of that individual, except for the primary morphology of the genome. Schematic representation of various types of morphologic anomalies compared to normal development. The defined terms are illustrated in Fig. If a term in the text is indicated in bold-italics, that term is listed and a definition is available.
#ANOMALY DEFINITION SERIES#
During a second series of e-mail and telephone conferences, final definitions and comments were established. In May 2013 the definitions were forwarded to an international group of experts (Elements of Morphology Consortium see appendix). During a series of subsequent e-mail and telephone conferences, the definitions were refined. The group convened at the National Institutes of Health in Bethesda on January 25–27, 2013 during which concept definitions were conceived. Each prepared an overview of existing definitions of the term, a literature review, and a proposal for a new definition. We divided the terms amongst the authors. We selected terms that were still in use (for example we did not consider the term “anomalad” as the term was discontinued in 1987 ). The present authors, all members of the Elements of Morphology group, used as source for the general terms the series of publications that previously defined these. We have added the adjective “morphologic” to the terms anomaly and variant to indicate this, although in daily practice in dysmorphology these terms may be used without this. We recognize that the terms (especially the terms anomaly and syndrome) are used in different ways within, and outside of, general medicine, but we limit our definitions to the description of human morphology.
#ANOMALY DEFINITION UPDATE#
In the interval since those publications, and the intervening developments of positional cloning and, now, massively-parallel sequencing, and concomitant advances in developmental biology, it became clear that an update was necessary. The history of prior efforts to define the terms considered here is reviewed separately. The present report describes the definitions of the general terms most commonly used to describe congenital anomalies in clinical practice and research. The reader is encouraged to consult the introduction when using the definitions. The original series was accompanied by an introductory paper describing general aspects of the project “Elements of Morphology”. Additional papers on the morphology of the limbs and trunk are in preparation. This is the eighth in a series of papers defining the morphologic variants of the human body.
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