MadSci Network: General Biology
Query:

Re: Can a fertilized egg(human being's) be considered as a human being?

Date: Mon Oct 1 11:19:34 2007
Posted By: Art Anderson, Senior Scientist in Immunology and Pathology at USAMRIID
Area of science: General Biology
ID: 1191247162.Gb
Message:

John,

Your question is rightfully controversial. There is no objective answer 
that can be proved or disproved. I will offer my opinion and I will try 
to stay within the limits of language. I will try not to make categorical 
statements that cannot be tested.

Both of the terms you use, Human and Being, reflect life outside of the 
uterus. The condition of being human is not just anatomical, it is also 
related to intellectual and physical attributes. The condition of being 
a "being" is connotes independence on another for existence. This is why 
scientists and physicians refer to stages of becoming a being. That is, 
first there is a fertilized egg, then a blastocyst, then an embryo, then 
a fetus, and only until the fetus reaches full term and is ejected from 
the uterus does it become a baby. As the baby develops in a nurturing and 
intellectually stimulating environment, it learns human traits and 
becomes a human being, in my opinion.

Statistically, 60% of all joinings of sperm and egg to form a fertilized 
egg fail to become embryos, fetuses or babies. This is because the 
process of development requires that each stage occurs perfectly or 
biological mechanisms monitoring cell growth and disposition will trigger 
spontaneous death of critical cells and the embryo and is either ejected 
or absorbed inside the uterus. A non-viable embryo or fetus ends its 
existence before it reaches stages where I would call it a human being.

In older human embryology books the phrase, "ontogeny recapitulates 
phylogeny" was used. It was thought, incorrectly, that from fertilization 
onward the developing forms resembled single cell organisms like amoebae, 
multicellular organisms like hydra, and complex primitive vertebrates 
like amphioxis, tadpoles and then mammals. This is because of the shape 
changes and the lack of resemblance of the products of conception to 
anything apparently human. However, by 12 weeks gestation a fetus, who by 
now has become like a parasite living on filtrates of the mothers blood 
that it obtains via a placenta, looks like a small model of what it will 
later become. It is totally dependent on the nutrition and oxygen it 
obtains from the mother and will die shortly after being disconnected to 
the mother via the placenta or if the mother consumes something that is 
toxic to it even if it may not be seriously toxic to her. 

Even while the fetus has a head, shoulders, arms, hands with finger, 
trunk, legs and feet with toes, it is not yet a human being to me. 
However, by the this time the mother and father of this fetus will have 
built up strong anticipations of what this fetus will become when it is 
born. Many fetuses are lost due to spontaneous abortion, called still 
birth, and the expectations the mother and father hold cause them to 
grieve for what might have been. I believe most people would think a 
fetus at this stage is a human being because of the emotional attachment. 
But, as the fetus is so dependent on being attached inside to the mother 
and because no one has ever described intellectual attributes of 
humanness in fetuses, I am not ready to say it is a human being, 
regardless that many grieve over the loss of a fetus. Fertilized eggs, 
blastocyts, and embryos are lost without anyone noticing although couples 
suffering from the condition of infertility probably would also grieve 
over the loss of an embryo.

The online dictionary Wikepedia provides some useful information that can 
help expand on what I have said about what is human and when in the cycle 
of life a fertilized egg, blastocyst, embryo, or fetus may become an 
human being. http://en.wikipedia.org/wiki/Hum
an

In earlier times, like during the colonization of North America, fetuses 
that reached full term and were born as babies often did not survive to 
reach 1 year of age. In some cultures newborns would never be placed on 
the ground because it was believed that this would hasten there demise. 
In these cultures, the family would hold a ceremony at 6 or 12 months to 
attest to the viability of this child and to begin to allow it to move 
around on the ground. This practice suggests to me that families may have 
postponed regarding the new born as human until it succeeded in postnatal 
survival. Even today, with better living conditions and better health 
care, a significant number of newborn babies die before they reach their 
first birthday. 

So, now it comes down to opinion. Do I regard a baby as a human being or 
not. I believe I do regard a baby, capable of living outside the womb, as 
a human being. It is clear that babies initiate and maintain a constant 
nonverbal and audible connection with its parents and caregivers. It 
learns and applies what it knows to improve its conditions and survival 
so, yes. I believe babies are human beings.

However, I do not believe fertilized eggs, blastocysts, embryos and 
fetuses (of age where survival outside the womb is not possible) are 
human beings. 

Many people will disagree with this determination. I have listed my 
criteria and reasons for the belief that I stated. I have tried to not 
repeat what others have told me or required me to say. I have not taken a 
purely emotional position based on expectations and aspirations; and, I 
have tried to provide expamples to support the opinion I stated. I 
believe, bodies of philosophers, physicians and ethicists such as the 
National Bioethics Advisory Commission, have arrived at similar positions 
but I am not merely adopting their position.   http://www.bioethics.gov/reports/past_commissions/nbac_cloning.pdf

Fundamentalist Christian organizations take the position that 
fertilization begins the life of a human being. As sperm are living, and 
the egg is living, life was present before fertilization. http://www.mtio.com/artic
les/bissar61.htm

Fertilization merely allows this life to have a complete set of 46 
chromosomes, one set of 23 from the father and another set of 23 from the 
mother. Taking an adult cell and tricking it into dividing in vitro would 
be a similar form of life but it would not become an embryo and it would 
certainly not become a human being. An adult cell taken from a woman with 
cervical cancer at Johns Hopkins early in the 20th century still lives on 
as the "HeLa cell line." Because this cell line has outlived the persons 
who isolated it, and continues to survive in research laboratories all 
over the world, would we say this cell line is a human being that has 
become immortal; of course not, But, for all intents and purposes it is, 
but it isn't a human being. 

My opinion is also not a legal decision, as judges may decide that a 
fertilized egg is a human being for purposes of prosecution in a trial as 
is expressed in this news report.  http://www.npr.org/templates/story/story.php?
storyId=4492781 I am not 
taking a legal position but proved this reference for your consideration.
 http://learn.genetics.utah.edu/units/cloning/clonezone/timeline_zone
.swf

So, John, it is up to you to draw your own opinion.

I hope the information I provided helps.



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