Definitively Defining Life: An Analysis by Dr. Condic

SOPHIA TRAN Perhaps one of the more pervasive issue topics in bioethics today is defining what makes us human. Developments in embryology and human embryo research now afford us the capability to look at things on a unicellular level, but do not provide people and scientists alike with a definitive answer of as to when human life starts. Dr. Maureen Condic, Associate Professor of Neurobiology and Anatomy at the University Of Utah School Of Medicine, presented a biological analysis of the lines that should be drawn between simply being a collection of human “cells”, and becoming a human “being”.

The biggest problem today concerns the continuity of embryonic development and the subjective commentary it attracts. There are many developmental benchmarks within the spectrum of zygotic development that are used to track normal growth of an embryo. As a result, people place markers at arbitrary points along this developmental timeline to decide when an embryonic structure may be considered a human being. Some believe human life starts at implantation, during the formation of a placental connection with the mother; others believe it begins with the establishment of self-awareness in the fetus. Aside from this subjective interpretation is a biological interpretation that examines the features that distinguish one cell from the other in human development.

The Fetus and the Lining of the Uterus - Leonardo da Vinci (1510-1512)

Condic maintains that a new cell is formed when there is either a change in cell type (change in material composition or gene expression), when there is a change in cell behavior, or both. An example proposed was the combined interaction between the sperm and egg. Gametes initially solely focus on reaching the other, undergoing fertilization, and fusing to produce a zygote. However, when this is achieved, the zygote takes on a new novel function, no longer independently focused, and thus differentiates itself in function compared to that of the prior gametes. Post-fertilization, the zygote adjusts ion concentrations in the area surrounding it, preventing excess sperm from intruding on the ongoing process of development. This segregation of novel functions, Condic says, is the basis for organismal function, in which there is specialization of two or more cells. Additionally, Condic believes that the very thing that makes us human is the organization towards the production of a mature adult. As such, she states this organization is already happening as early as the four-cell stage in embryonic development, as specialization and fetal development start nearly as early as fertilization occurs.

Condic’s goal is not to create a philosophical rift. Instead, she says that while defining life is still very much a topic of personal preference and belief, bioethics should be looked at objectively. Presenting a scientific view on a deeply divided moral and ethical issue is tough, as much of the public already holds a strong personal opinion. Regardless of her intentions (or lack thereof), her findings do however noncommittally support one side of the embryonic research discussion.

Based on Condic’s testimony, should all matters of bioethics be grounded in textbook definitions and scientific thought? To what degree should human subjectivity play a role in the determination of what defines who we are as a species? Condic’s proposed idea of humans-at-zygote level is compelling, but only briefly explores the fundamental question that is the main source of conflict in bioethics as it relates to our changing society today: where should lines be drawn? Studies like hers address undeniably important questions in a new age where ethical issues grounded in science can provide effective means of argumentation and discourse now and in the future.

Further reading:

http://bdfund.org/wordpress/wp-content/uploads/2012/06/wi_whitepaper_life_print.pdf

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