Broad Support for "Y" Men Are Men

Sex in humans is determined by the fact men carry one X chromosome and one Y chromosome in each cell, while women carry two Xs.

David Page of the Whitehead Institute has recently shown that Y chromosomes can repair its own genes in an experiment that denied the Y chromosome the benefits of recombining with the X.  The result was that the Y recombined with itself.  Dr. Page's team also found 78 active genes on the Y, contradicting earlier impressions of the chromosome as being a genetic wasteland apart from its male-determining gene.

In related news, MIT and Harvard announced today the formation of The Broad Institute whose purpose will be to fulfill the promise of the Human Genome Project for medicine.  As Charles M. Vest, president of MIT noted, “This venture will be an important nexus of Boston and Cambridge’s contributions in the future. We are deeply grateful to Eli and Edye Broad for their visionary commitment ($100m immediately) and for their extraordinary leadership as philanthropists." 

Faster than a Speeding Gene

Most people forget that we've only mapped the complete genome of a few people.  Although significant, the real breakthrough will come from population level analysis of genetic variation. 

The International HapMap Project is doing just this.  Haplotypes are genetic sequence blocks that are shared by many people.  Once these haplotypes are mapped it will form a powerful shortcut to identifying inherited gene sequences linked to disorders such as diabetes, heart disease and cancer.

Biomedical breakthroughs extending life and health are closer than we think. The aggressive timeline for the Human Genome Project started in 1990 was 15 years.  It was completed in 10.  What projects are being worked on now that will move much faster than most expect? 

Neurotechnology before Genetic Engineering

Bill McKibben's brave new book, Enough: Staying Human in an Engineered Age explores (excerpt) how human genetic technologies will soon give scientists the ability to re-engineer our children, undermining our common humanity, and leading to a 'posthuman' future.

The human germ-line engineering debate continues to capture the popular imagination, sitting at the core of bioethics debates, while neurotechnology quickly slips into existence.

It is my firm belief that neurotechnology's ability to provide tools that can temporarily influence human emotional, cognitive and sensory states via neuroceuticals will have more profound implications for humanity, in a much nearer time frame, than genetic engineering for several reasons:

• Regulation and distribution systems are in place:  The FDA and pharmaceutical development and distribution systems are already globally refined, tested and trusted processes
  
• Social acceptance is proven: Humans are already using early forms of neuroceuticals on a vast scale.  For example, 17% of the US white-collar work force is currently using anti-depressants. 

Humans will perform germ-line engineering on other organisms on vast scale, but human germ-line engineering won't become widely accepted until significant experimentation with less permanent tools helps people learn exactly what traits they would want their progeny to exhibit. 

Moreover, as neurotechnology becomes more precise and flexible, it may indeed turn out that humans will choose neurotechnology over genetic engineering to enhance themselves and their offspring.  Instead of debating the bioethics of germ-line engineering, we really should be focusing on the neuroethics of neurotechnology.

What is a gene?  Really.

Now that the human genome has been sequenced it is time to return to simpler questions, like what is a gene?

• In the early 1900s, a gene was as an abstract concept to explain the hereditary basis of traits. 
  
• In the 1930s, Beadle introduced the concept of "one gene, one enzyme," which later became "one gene, one polypeptide."
  
• Today, a gene is defined in molecular terms as "a complete chromosomal segment responsible for making a functional product."  For more detail, see this week's Science.

Sequencing the genome is just the first step in a much larger project Human Biology Project.  As Eric Lander of the Whitehead Institute reminds us, "starting today, the real serious analysis of things can begin."

Powered by faster gene chips the cost of genetic analysis continues to plummet. At the beginning of the project "it cost $10 to definitively identify a single base pair... and a highly trained technician could scan perhaps 10,000 base pairs in a day. Now the equivalent cost is 5 cents and lightning-fast robotic sequencers routinely process 10,000 base pairs a second."   Now that's progress.  Next step, sequencing the proteome.

Evolution IS a Fact

Other than my concern that Post Traumatic Stress Syndrome may eventually overtake depression as the leading global mental health problem, Richard Gayle's blog today on evolution tops my list of memes that deserve repeating.

We again have people rejecting textbooks because the books discuss evolution but not creationism. Evolution is a fact. It is the foundation upon which modern biology rests. Trying to pretend differently (as one of the Board members said "I do not believe that we evolved from anything other than human beings") only hurts the students and furthers ignorance. It does not reflect well on Tennessee. But then it was the state that outlawed the teaching of evolution, leading to the Scopes Trial.