From Chapter 1 of The Ethical Brain:

...is it right to attribute the same moral status to that human embryo that one attributes to a newborn baby or, for that matter, to any living human? ... The implications of determining the beginning of moral status are far-reaching, affecting abortion, in vitro fertilization, biomedical cloning, and stem cell research. The rational world is waiting for resolution of this debate.

Gazzaniga here frames a debate separate from the beginning of human life. In this debate, it is possible to believe human life begins at conception and still support ESC research, abortion, IVF, and/or cloning. What matters in this debate is whether an embryo in a particular stage of development should receive the same moral respect given to a newborn baby.

A good many people would still argue yes. It is common for those who base their argument on the continuum point of view to confer full moral status on the zygote, believing that any other decision is arbitrary and unfounded.

Others might accept the continuum, but assign varying degrees of moral status based on embryonic or fetal development. Like Hans Martin Sass, who looked at established definitions of brain death and reasoned that society could reach a consensus for protecting embryonic life by applying similar criteria for brain life, many look to brain development for guidance.

The embryonic stage reveals that the fertilized egg is a clump of cells with no brain; the processes that begin to generate a nervous system do not begin until after the fourteenth day. No sustainable or complex nervous system is in place until approximately six months of gestation.

Others ignore it completely:

The fact that it is clear that a human brain isn't viable until week 23, and only then with the aid of modern medical support, seems to have no impact on the debate. This is where neuro "logic" loses out. Moral arguments get mixed in with biology, and the result is a stew of passions, beliefs, and stubborn, illogical opinion.

Sass, incidentally, theorized that prior to the beginning of cortical neuro-neuronal synapes (70 days after conception) abortions and presumably stem-cell research would be morally permissable. Sass's thesis is a cautious one, as any thesis should be if it hopes to achieve any degree of consensus in this debate. As Gazzaniga points out:

The brain at Carnegie Stage 23 [approximately eight weeks], which has slowly been developing from roughly the fifteenth day, is hardly a brain that could sustain any serious mental life. If a grown adult had suffered massive brain damage, reducing the brain to this level of development, the patient would be considered brain dead and a candidate for organ donation.

Still, the argument goes, brain death signifies the end of something. The early stages of brain life signify the beginning of something, and that something is a human being and should be both respected and protected as such. These arguments overlook the fact that up to 80% or more of embryos never implant; that it is an enormous stretch to believe that God or nature endows every single zygote with a human destiny only to kill 80% of them by the 10th day. How perverse is that?

Also ignored is the fact that twinning usually occurs in the first fourteen days, as does the much rarer event of two separate embryos merging into one to form a chimera. In these cases, we have either one individual "human being" splitting into two separate "human beings," or two separate "human beings" merging into one individual "human being." Do you see the fallacy of arguing that these are actually human beings before such drastic changes occur?

Gazzaniga takes these arguments into much greater detail in this chapter. I urge everyone interested in stem-cell research, abortion rights or just bioethics in general to read it. If nothing else, it will certainly force you to consider some provocative questions.

I myself continue to agree with Gazzaniga that "assigning equivalent moral status to a fourteen-day-old ball of cells and to a premature baby is conceptually forced. Holding them to be the same is a sheer act of personal belief."

Michael Gazzaniga, widely considered the "father of cognitive neuroscience" and member of the President's Council on Bioethics, in his most recent book, The Ethical Brain, tackles the moral dimensions of neuroscience. Gazzaniga, who directs the Center for Cognitive Neuroscience at Dartmouth College and is a member of the President's Council on Bioethics, says, "We need a moral compass, and neuroscience has things to say about important ethical issues that affect everyone."

Science and the City, the Web site for the New York Academy of Sciences, offers highlights from an Academy-sponsored public conversation between Gazzaniga and author Tom Wolfe that took place last June. While the highlights from this dialogue are interesting in their own right, what most intrigued me on that page was its link to a chapter from Gazzaniga's book.

In the excerpt from Chapter 1 -- Conferring Moral Status on an Embryo -- Dr. Gazzaniga asks and then attempts to answer the question: "When should we call an embryo or a fetus one of us?"

I'll spend a little time on this in the next post.

Knowledge Networks for the Genetics & Public Policy Center reports that 66.66% of Americans favor embryonic stem-cell research. As reported by Angus Reid Consultants, the survey results broke down as follows:

• Strongly approve - 21.6%
  
• Approve - 45.0%
  
• Disapprove - 16.7%
  
• Strongly disapprove - 14.6%
• Don’t know / No answer - 2.1%

With the President vowing to veto the legislation if it includes federal funding, and ongoing concerns about Hurricane Katrina, the Harriet Miers Supreme Court nomination and PlameGate, the Senate has postponed voting on this issue until early 2006.

This has been a good month for major breakthroughs in stem-cell research. According to ScienceDaily , on October 11th, "University of Minnesota scientists, in groundbreaking research, say they have used human embryonic stem cells [ESCs] to kill cancer cells."

This is especially good news since opponents of the research like to argue that ESCs have yet to cure anything. (They ignore the fact that progress has likely been hindered by embroiling researchers in emotionally charged moral debates.)

"This is the first published research to show the ability to make cells from human embryonic stem cells that are able to treat and fight cancer, especially leukemias and lymphomas," said Dr. Dan Kaufman, an assistant professor of medicine in the university's Stem Cell Institute and lead author of the study.

The good news continued on October 20th, when Science Daily reported another breakthrough, this one at Johns Hopkins, where "scientists say they've discovered the presence of functional ion channels in human embryonic stem cells." The discovery offers hope to researchers for blocking "potential tumor development," one of the problems encountered with grafting ESCs in the past.

According to Ronald Li, an assistant professor of medicine at Johns Hopkins School of Medicine and senior author of the study, "Our discovery of functional ion channels ... provides an important link to the differentiation, or maturation, and cell proliferation, or growth of human ESCs."

One can only hope that these advances convince some fence-riders that they can no longer ignore ESC's potential benefits.

As the New York Times reported yesterday, South Korea continues to shame the United States with their rapid advances in stem-cell research. The Koreans announced they will "set up a worldwide foundation to help create embryonic stem cells for medical research."

The World Stem Cell Foundation will have satellite clinics in San Francisco and in England. The clinics will clone stem cells "for any scientist who wishes to establish a research culture of cells from patients suffering from particular diseases." The actual cloning will be done by Korean scientists who will visit the clinics for that purpose.

"Cloning of diseased cells is now seen as one of the most promising applications of embryonic stem cell research." The Korean scientists should be applauded for unselfishly sharing this technology. Their vision brings hope to the millions suffering from currently incurable diseases.

The Los Angeles Times reports that "Supreme Court nominee Harriet E. Miers told a conservative group in 1989 that she opposed abortion and would 'actively support' legislation to severely restrict the procedure should the Supreme Court overturn Roe vs. Wade." So this was the confidential information that Dr. James Dobson said explained his support of Miers' nomination.

Earlier this month, Dobson told Focus on the Family radio listeners "When you know some of the things that I know--that I probably shouldn't know--you will understand why I have said, with fear and trepidation, that I believe Harriet Miers will be a good justice." He was referring, of course, to his telephone conversation with Karl Rove, during which Rove somehow assured Dobson that Miers was great for conservatives. Since the papers released by the White House to the Judiciary Committee contained Miers 1989 comments, it's not a stretch to imagine their inclusion in the Dobson/Rove conversation.

What do we make of those rare instances in which two non-identical twin embryos merge into one? The resulting chimera can contain different sets of chromosomes from four gametes -- two eggs and two sperm. This anomaly can cause faulty DNA testing (especially if the merged embryos were the same sex), because most of the body may contain one set of chromosomes, while the other set may be found in only one or two organs.

This is what happened to Lydia Fairchild, who had to go to court to keep her children after DNA testing showed they weren't hers. It wasn't until doctors took a cervical smear that they discovered Lydia was a chimera with 2 separate female DNA strands. Because DNA testing is relatively new, and also because it's not usual for people to have their DNA tested, same-sex chimeras may be more numerous than previously believed. Unless they develop an abnormality like skin discoloration or different eye colors, same-sex chimeras look perfectly normal.

It's easier to determine chimerism if the merging embryos are different sexes because genitals of both sexes are formed. Sometimes one sex is dominant, like the newborn who appeared to be male, but was found to have an ovary and a fallopian tube.

So why this discussion of chimeras? Well, for one thing, if the original two embryos were destined to become certain unique individuals, this merge could not happen, especially since embryos of opposite sex can merge. Were the multiple embryos destined to become a single embryo all along? If so, which set of chromosomes determined the merge?

If human life begins at conception, then how many souls does a chimera possess? Let's reverse the questions I posed about twinning: if a zygote is destined to merge with another zygote, does each of the original fertilized eggs possess a soul? Further, does the chimera contain one soul or two? We cannot argue that one twin dies, because the resulting embryo contains DNA from two distinct embryos.

Until it is determined that an embryo is going to develop into a single unique human being, how can we invest it with personhood? As I've repeatedly said, at the blastocyst stage, when stem cells are taken for research, the embryo is not guaranteed to become a person. It can spontaneously abort (as do half or more), it can split into two or three individual embryos, or it can merge with another embryo to form one.

Ignoring the realities and anomalies of science does not make them go away. Refusing to ask tough questions because they do not support one's preferred belief is hardly ground for a sound argument. It may be comforting to believe something "just because," but that does not make that belief true. When human life begins is a very tough question. Simple assertions of belief are easy. Searching for the truth is not.

Although identical twins are from the same fertilized egg and share the exact same DNA, their fingerprints are always different. Apparently, fingerprints are not predetermined in the zygote.

So how do we reconcile this fact with the idea that the fertilized egg is a unique human being? In the case of identical twins (or even triplets), that zygote is not a unique human being. Or if it is, and if human life begins at conception, then it must be more than one unique human being. But I find it problematic to argue that the zygote is two or three unique human beings before it even splits. So what is it?

And what about the fingerprints? Are they pre-determined or do they appear by chance? If they're pre-destined, then the twins or triplets must be pre-destined also. But why do some zygotes split as early as eight days and some as late as sixteen days?

And what of ensoulment? If the fertilized egg is a unique human being, as is argued by the Catholic Church and others who designate themselves pro-life, then does it have a soul at that time? If it is a zygote destined to split into two or three embryos, does the original fertilized egg possess multiple souls? Or do the souls enter the embryo after the split? If that's the case, then human life cannot begin at conception because at that point, we're not even sure how many embryos there will be.

If anyone has some thoughts about this, I look forward to hearing them.

Next: And Two Become One -- Chimeras

Referencing Mike's October 6th post about Harriet Miers and gays, it sounds like the Houston Chronicle didn't print the whole story. Here's the Chronicle's version:

Civil rights: Miers favored equal civil rights for gays when she ran for Dallas City Council, and said the city had a responsibility to pay for AIDS education and patient services. But she opposed repeal of the Texas sodomy statute — a law later overturned by the Supreme Court. In a survey for the Lesbian/Gay Coalition of Dallas, Miers provides a hint of her thinking on homosexual rights issues. Miers answered Yes to: Do you believe that gay men and lesbians should have the same civil rights as non-gay men and women?

Now, here's a direct quote from Molly Ivins that paints a different picture of Miers' run for City Council:

She ran for city council in 1989 as a moderate, but struggled during her interview with the lesbian/gay coalition. (At the time, it would have been considered progressive to even show up.) The Dallas Police Department did not then hire gays or lesbians, and when asked about the policy, Miers replied the department should hire the best-qualified people, the classic political sidestep answer.

When pressed, she said she did believe one should be able to legally discriminate against gays, and it is the recollection of two of the organization's officers that the response involved her religious beliefs.

So, sounds like Harriet tried to have it both ways, and, considering how most of the media reported it, she pretty much did. But since Ivins knows Texas politics as well as the rest of us know our own names, I'll go with her version.

I apologize that I haven't posted anything in almost a week. For some unknown technological mystery, our Internet service was down for several days. I want to continue my thoughts on twins (plus respond to Mike's post), but for now I'll post a column published by the Tallahassee Democrat, on October 1st.

Stem-cell research opponents are silent on fertilization

The Tallahassee Democrat's editorial on Florida's new stem-cell initiative [Sept. 23] was welcomed by supporters of embryonic stem-cell research. However, one point needs clarification. The majority of those who oppose embryonic stem-cell research on ethical grounds do not believe the cells hold "the potential for human life." They believe the cells are human life.

Former House Majority Leader Tom DeLay has said, "An embryo is a person." President Bush refers to embryos as "real human lives."

I have a problem with this. If I believed that embryos were "real human lives," I'd be mighty uncomfortable knowing that, in the United States alone, about 400,000 little "babies" are frozen solid, side-effects of the in vitro fertilization (IVF) process.

I'd be even more uncomfortable knowing that almost 9,000 wait to be discarded or destroyed, not to mention the inadvertent casualties. The American Society for Reproductive Medicine estimates that "about 65 percent of these embryos will survive the freeze-thaw process." Others put that number closer to 50 percent.

Where is the outcry over the creation of these disposable "human lives"?

The ethical position seems to be: It's OK for laboratories to create excess "human lives." It's also OK for these extras to be destroyed. But it's a sin to use them for research with the potential to help the 128 million living Americans now suffering from diseases targeted by that research?

Florida's initiative states that researchers will have access only to those embryos that "before or after formation, have been donated to medicine under donor instructions forbidding intrauterine embryo transfer." If not implanted or used for research, these embryos would presumably be discarded.

How can I state this more clearly? They would be discarded.

Opponents of this research, including the president and our governor, are saving nothing. As one father of an adopted embryo put it, "our 'culture of life' perversely demands that they be thrown into the garbage. That's how precious they are ... we must destroy life, according to the administration, to avoid preserving life."

Until opponents of stem-cell research address the total picture - IVF destroys more embryos than stem-cell research - their opposition rings hollow. If they won't act to outlaw IVF, how can they continue to oppose using IVF's discards for life-saving research? I still seek the moral sense of that position.

Some opponents of stem-cell research persist in using terms like "murder," "dismemberment" and "slaughter," apparently ignoring what happens to the leftover embryos no one seems to want. (And before you shout Snowflake babies, born through embryonic adoption, the numbers don't work. Fewer than 100 to date.)

That argument aside, what do researchers actually "murder?" Stem cells are taken from very early-stage embryos, usually 4 to 5 days old, that have been fertilized in vitro, in a petri dish. Called blastocysts, these microscopic balls of cells are roughly the size of the period at the end of this sentence.

At this point in their development, the cells in the blastocyst have no characteristics of a specific type. They are not yet purposeful as a heart cell, skin cell, kidney cell, etc. They are non-specialized cells with the potential to differentiate. But before differentiation, which occurs at about day 10, many things can happen.

The fertilized egg might fail to attach to the uterine wall, which happens more often than not, causing it to pass. The fertilized egg might split and become identical twins. It might merge with another fertilized egg to create the unusual scenario of two fertilized eggs developing into a single embryo, resulting in a chimera. Or, the fertilized egg could develop into a single human being.

Until differentiation, it has no clear "fate" or "destiny." Yet this is what opponents to embryonic stem-cell research prioritize over living, breathing human beings desperately waiting for cures.

Morality is never black and white, although many live their lives trying to prove it is. Shades of gray have a tendency to creep in at inopportune moments, forcing us to question long-held beliefs, to wonder if we were right (or wrong) all along.

It's like the question posed so often in this debate: If the clinic caught fire, would you save your 2-year-old or that Petri dish of newly fertilized eggs? Taking the moral high ground is easy when you have nothing to lose. It's harder to stay there once the sky turns gray.

I don't disagree in thinking Miers would be a poor, poor choice for the Supreme Court. But in her defense her "resume" (if you can call it that) can be easily spun as more liberal. For example:

Miers favored equal civil rights for gays when she ran for Dallas City Council, and said the city had a responsibility to pay for AIDS education and patient services...In a survey for the Lesbian/Gay Coalition of Dallas, Miers provides a hint of her thinking on homosexual rights issues. Miers answered Yes to: Do you believe that gay men and lesbians should have the same civil rights as non-gay men and women?

(as printed in the Houston Chronicle). So they should have the same rights. That sounds pretty...oh, liberal, to me.

About five years I was dating this girl named Laura. I was sitting on the front porch (alone) with her dad in complete, miserable silence. He broke the awkwardness by asking a simple question--the first words he had ever spoken to me. "Son. Are you a pervert or a liar?" "Pervert." I replied. "Me too." My sex life aside, I don't think there is anyone who wants to hear from a liar. Sorry, W. Toni was dead on when she said I cannot imagine W nominating someone to the court without knowing how she stands on critical issues. She's right. Mr. President I'm really pissed off that you think that we peasants are so stupid. If she was all for abortion she wouldn't a) be your lawyer b) be your nominee. You've been pulling these stunts off for so long you're getting a little too cocky.

My (current) girlfriend's father is a Public Defender. He is also seeping his faith. Yet when he goes to trial he just shuts it off. Completely. He is just a walking law book without any sort of personal affiliation with God. Once the tie comes off, he's back to "normal". Here's the ultimate reason no one will be happy with Mrs. Miers: Side A wants a strict, by-the-book, justice capable of putting his/her own feelings aside when working the bench. Side B wants someone capable of looking inward and doing "what is right". Miers accomplishes the goals of neither side and now both sides want someone else. If we're going to have a nominee that makes all of American grimmace you might as well put someone dreamy like Teri Hatcher.

Supreme Court nominee Harriet E. Miers attends an evangelical Christian Church opposed to abortion. A member of the Valley View Christian Church in Dallas for twenty-five years, Miers was also part of an initiative to overturn the American Bar Association's support of abortion rights in the early 1990s.

According to the L.A. Times, Miers gave $150 to Texans United for Life in 1989 and was a sponsor of their annual dinner that honored Rep. Henry J. Hyde (R-Ill.), a leading congressional opponent of abortion. As Molly Ivins reports, Miers was pro-choice when a young woman, but later changed her mind as a result of a Christian experience of some kind.

I'm concerned because it's hard to believe that someone's evangelical beliefs would not color their interpretation of law. I know, I know. Justices are supposed to be able to rise above such things, but in my experience, human nature trumps idealism a good part of the time.

When Miers ran for Dallas City Council in 1989, she fielded questions from the lesbian/gay coalition on the police department's policy of not hiring gays or lesbians. Again according to Ivins, Miers said she did believe one should be able to legally discriminate against gays, and it is the recollection of two of the organization's officers that the response involved her religious beliefs.

As if all that isn't enough, the fact that she's worked closely with President Bush for over a decade should raise alarm bells for pro-choice advocates. Forgive my cynicism, but I cannot imagine W nominating someone to the court without knowing how she stands on critical issues. (He obviously doesn't overly concern himself with credentials.) And abortion is definitely important to this "pro-life" (I prefer anti-choice) president.

The warning signs are there. Not least among them is this snippet from The National Review's David Frum: In [a] White House that hero-worshipped the president, Miers was distinguished by the intensity of her zeal: She once told me that the president was the most brilliant man she had ever met.

And if that doesn't scare you...

Twins have intrigued us since the legendary Romulus and Remus supposedly founded Rome. Stories of twins separated at birth living nearly identical lives; twins' secret languages; the sense of incompleteness that haunts a surviving twin, sometimes for life; all are part of the twins' mythology. In addition to their lore, twins also bring another component to the "beginning of human life" question.

In the past two decades, the number of multiple births in the United States has jumped dramatically. Between 1980 and 2000, the number of twin births has increased 74 percent, and the number of higher order multiples (triplets or more) has increased fivefold, according to the National Center for Health Statistics. Today, about 3 percent of babies in this country are born in sets of two, three or more, and about 95 percent of these multiple births are twins.

Read the entire article here.

Fraternal twins form when two fertilized eggs implant at the same time. (The eggs are fertilized by separate sperm.) Also known as dizygotic twins, they develop separately, with separate chorions and separate amnions , although they may share the same placenta. Genetically as different from each other as any other siblings, they can even have different fathers. Approximately 72% of twins born in the U.S. are dizygotic, and about 30% of them are of opposite sex .

Identical twins are, to me, a little more interesting. These twins, known as monozygotic, are much rarer than dizygotic twins; only 3-5 per 1000 are born worldwide. Monozygotic twins form when one sperm fertilizes one egg and then splits into two separate embryos. Why the zygote splits is a mystery, although there is speculation that “monozygotic twinning may be a teratologic event” Identical twins have the same DNA and can only be the same sex.

Monozygotic twinning presents a problem for those who believe that human life begins at conception. With identical twins, conception creates only one fertilized egg (zygote), a single human life for those who subscribe to this belief.

What does it mean, though, when that human life suddenly splits and forms another, genetically identical, “human life”? Did that human life begin at conception? And if theories linking monozygotic twinning to teratogens are true, then the second twin did not exist until the original zygote was affected by the teratogen. You might even call the second twin a chemically induced embryo, although technically, it is a clone.

To be continued