Fitness Blog

Thanksgiving Remembrance: Mayflower Medicine.

Any Excuse Will Do: Any excuse to justifying prejudice, or to stir up fear mongering of what may come:

At the same time, genetic information is slipping out of the laboratory and into everyday life, carrying with it the inescapable message that people of different races have different DNA. Ancestry tests tell customers what percentage of their genes are from Asia, Europe, Africa and the Americas. The heart-disease drug BiDil is marketed exclusively to African-Americans, who seem genetically predisposed to respond to it. Jews are offered prenatal tests for genetic disorders rarely found in other ethnic groups.

Such developments are providing some of the first tangible benefits of the genetic revolution. Yet some social critics fear they may also be giving long-discredited racial prejudices a new potency. The notion that race is more than skin deep, they fear, could undermine principles of equal treatment and opportunity that have relied on the presumption that we are all fundamentally equal.

"We are living through an era of the ascendance of biology, and we have to be very careful," said Henry Louis Gates Jr., director of the W. E. B. Du Bois Institute for African and African American Research at Harvard University. "We will all be walking a fine line between using biology and allowing it to be abused."

We have been living in an era of ascendant biology since Darwin. Remember eugenics? Jews have been offered prenatal testing long before the mapping of the human genome, as have African-Americans. But prenatal screening is not quite the same as the eugenics movement heyday.

So why the hyperventilating? It turns out that the Times is taking its cue from blogs commenting on studies studies like this. Well, if the blogs say that genetics justifies prejudice, it must be true! I never thought I would see the day that the New York Times took that attitude on its front pages. It must be part of their plan to join the internet age. Here's the part that's gotten the Times convinced that genetics is going to bring back the days of institutionalized prejudice:

There exists a publicly available gene database, The HapMap Project, that contains random samples of genetic sequences from people in China, Japan, Nigeria, and people in the United States with European ancestry. It’s now possible to search the HapMap database for genes that have been linked with intelligence in published scientific studies. In this manner, we can determine if high intelligence genes occur with greater or lesser frequency in the various races.

Now, here’s an interesting point. If even a single gene correlated with intelligence occurs with different frequencies in the different races, this alone proves that there are racial differences in intelligence. How is that? Well, the egalitarian theory holds that every race has identical intelligence. Therefore, whatever genes there are that affect intelligence, they must be distributed exactly equally in all human races. Once even a small race difference is proven, the egalitarian theory is proven false. At that point, it’s only a matter of determining which race has the higher average intelligence based on the genetic evidence.

Oh, please. Here's a take home lesson for everyone on the science of genetics, and one that should never be forgotten - these studies are about associations of genes with traits, not the concrete coding of a trait by a given gene. Just because a locus on a chromosome can be found more often in people with schizophrenia than in the general population doesn't mean that everyone with that genetic code in that spot will have schizophrenia, anymore than it means that every sibling of a schizophrenic will have the disease. Ditto with intelligence. Ditto, too, with cancer risks and most other traits and diseases human genome mapping is linking to genes. The essence of a man is not written into his DNA.

Here's another important point to remember - our science is still young and uncertain:

These genomewide association studies have been able to examine interpatient differences in inherited genetic variability at an unprecedented level of resolution, thanks to the development of microarrays, or chips, capable of assessing more than 500,000 single-nucleotide polymorphisms (SNPs) in a single sample. This "SNP-chip" technology capitalizes on a catalogue of common human genetic variations that is provided by the HapMap Project, which was made possible by the completion of the consensus human-genome sequence...

....The main problem with this strategy is that, because of the high cost of SNP chips, most studies are somewhat constrained in terms of the number of samples and thus have limited power to generate P values as small as 10–7. In addition, most variants identified recently have been associated with modest relative risks (e.g., 1.3 for heterozygotes and 1.6 for homozygotes), and many true associations are not likely to exceed P values as extreme as 10–7 in an initial study. On the other hand, a "statistically significant" finding in an underpowered study is more likely to be a false positive result due to chance than is such a finding in an adequately powered study, and "statistically significant" associations could be attributable to systematic bias (e.g., from confounding due to ethnic ancestry, also known as population stratification). Thus, the sine qua non for belief in any specific result from a genomewide association study is not the strength of the P value in the initial study, but the consistency and strength of the association across one or more large-scale replication studies. Robust replication should permit the identification of true positive results and the weeding out of false positive results.

In other words, take these genome studies that link intelligence and race just as about as seriously as you would take studies linking intelligence to sex, or that predict elections with brain scans.

UPDATE: Best of the Web draws an important distinction:

Note that "the presumption that we are all fundamentally equal" is quite different from the notion "that all races are equal." The former is a moral principle, a premise about the basic dignity of every individual; the latter is an empirical presumption about group averages in measurable traits. Someone with an IQ of 80 is as human as someone with an IQ of 120; and this is so regardless of whether the average IQ of one race is different from that of another.

What worries people like those in the Times story is that racial differences in IQ or other traits seem to lend empirical support to racist theories. But those theories are qualitatively wrong, so that no empirical evidence could make them right. If all individuals are of equal dignity and worth regardless of IQ, then a group is not fundamentally superior or inferior to another group by virtue of differences in average IQ.

It seems that some very smart people mistakenly think that intelligence is a measure of fundamental worth. Maybe they're a little too impressed with their own brilliance.

In Remembrance:
Winged Victory

Veteran's Day movie recommendation - Wooden Crosses.

Veteran's Day medical reading - the influence of World War I on heart surgery.

A Word About MRSA: I've been fielding a lot of doorknob questions about MRSA lately. (Doorknob questions= questions thrown out just as my hand reaches the doorknob to leave the room.) Little wonder. It's been in the news again and again, and has even prompted the closing of schools and cancelling of football games. Despite what some editorialists say, it is being framed as a threat to our children. Here's an example of the typical coverage:

A 16-year-old Springfield High School junior remained in serious condition Friday in the intensive-care unit of Akron Children's Hospital with a drug-resistant staph infection. Michael Forester of Lakemore was hospitalized Oct. 24 and was to undergo surgery Friday, said his mother, Mary Baxter. "The more prayers I can get, the better," Baxter said Friday at the hospital.

On Wednesday, Springfield School Superintendent William Stauffer, in a letter sent to parents, acknowledged that a student had become ill and was admitted to the hospital. The superintendent said rumors that the student has a contagious disease that puts other students at risk and that the high school has an ongoing problem with staph infections are not true. Stauffer could not be reached for comment Friday.

What is this MRSA? A better question might be "What is SA"? The "SA" in MRSA is Staphylococcus aureus, a bacteria that resides in our nasal passages and skin. That is it's habitat. Normally, it causes us no problem, but if conditions are right, it can make us quite ill. It's often the culprit behind boils and styes and cellulitis and urinary tract infections. It can also cause more serious infections such as pneumonia (as in the case of the young man in the linked to article above), meningitis, sepsis, endocartditis, and osteomyelitis. It is one of the most common causes of sepsis. Penicillin conquered Staph infections for a little while, but the bacteria acquired resistance within a few years of the antibiotic's introduction. When penicillin became widely used in the community, the population of Staph aureus living in noses and on skin shifted toward those containing an enzyme that could cut the betalactam ring on penicillin, rendering it ineffective. New antibiotics were developed to get around this. One of those antibiotics was methicillin, which brings us to the "MR" part of "MRSA".

We don't use methicillin any longer. We use drugs like Augmentin instead. But, when we say that a Staph aureus infection is "methicillin resistant" we mean that it's resistant to all penicillins, even those that were developed to get around the betalactam-eating defenses of the Staph aureus population. This doesn't mean that it's resistant to all antibiotics, however, just the ones that we typically use for a Staph infections. In the hospital, we often use vancomycin for MRSA infections. In the outpatient setting, we use drugs like Bactrim and clindamycin. In most cases, the infections respond nicely to these drugs. There is, however, concern that the bacteria may one day develop resistance to these, too, as we use them more to treat the growing resistant population of Staph.

So here are the take home points about MRSA:

1) It isn't running amok in our schools like the blob or killer tomatoes. It's living on our skin and nasal passages just as it always has before it developed resistance to penicillin and its cousins.

2) One of the reasons bacteria acquire resistance is because we expose them to antibiotics when we don't need to. Don't insist on an antibiotic for every runny nose, even if the snot is yellow. And don't insist on one of the special antibiotics for MRSA for every pimple or pustule or red scratch. If we overuse our remaining effective antibiotics, we'll only end up with a population of Staph aureus that is resistant to those, too.

3) Don't freak out if you or your child develops a skin infection. Most staph infections are easily treatable. Even most MRSA infections are easily treatable.

4) When you read the newspaper, always remember that they lean to the dramatic in all things. It makes for more entertaining reading.

Trusty Dentist: Not so trusty with music and a drill.