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Biology Culture Sports Medicine

Testosterone: Epitestosterone Ratio: Cheating or Genes?

(repost from 01/2011)

The Case Against Lance Armstrong” is the title of an article in the January 24, 2011 issue of Sports Illustrated. The case that is made within this article is based on in large part on what a few people with gripes against Lance have said. The other “hard” evidence is based on several tests detailing a very high Testosterone:Epitestosterone ratio. Before 2005 the tests normal was considered up to 6:1 and was then lowered to 4:1. Several tests over the years, which may have been Lance’s were considerably higher than this.

According to SI “Three results stand out: a 9.0-to-1 ratio from a sample collected on June 23, 1993; a 7.6-to-1 from July 7, 1994; and a 6.5-to-1 from June 4, 1996.”

Each time the ratio was found to be high, the “B” Sample was tested and found to not confirm the preliminary test. The second test is usually a carbon isotope test that is more specific to studying the makeup of the individual’s testosterone.

While the article goes on to say that one high number (of the T:E ratio) should be a once in a blue moon occurrence, there are significant genetic factors that can come into play.  A 2008 article published in The Journal of Clinical Endocrinology & Metabolism titled “Doping Test Results Dependent on Genotype of UGT2B17, the Major Enzyme for Testosterone Glucuronidationshowed that if an individual had two alleles for the UGT2B17 gene, there was a large chance that they would not test positive for cheating even after having taken a large dose of synthetic testosterone. The estimates were that 40% of individuals could pass the ratio examination just by virtue of having two copies of this gene. On the other hand with mixed alleles (ins/del) or in the absence of  this allele there was a fair chance that the ratio would always be abnormal. Estimates were that in a normal population, up to 9-14% of people would have a false positive result and fail the test.

It seems that if you have the del/del or ins/del variations of alleles, you are going to pretty consistently fail the test. The authors suggest that this gene should be tested and the results modified based upon the genotype of the individual.

Understanding the purpose of the Testosterone:Epitestosterone ratio testing and doing at least a brief look at  factors that might affect this test, not just once but repeatedly are important when an article such as the SI one is written. This specific gene and its implication on testing is widely known and has been covered in a variety of journal articles. The Canadian Medical Journal detailed, in an editorial titled “Doping, Sport, and the Community“, the difficulties in testing for Growth Hormone abuse and Testosterone. The editorial also mentioned research I came across elsewhere which indicated that many Asians (up to 40%) had the version of this gene that would give a false negative.

So, let’s get all the evidence out. And let’s make sure the public sees all the scientific information on the validity and the problems that exist with this particular test. For another perspective on heroes in American culture, you can seek out one of George Carlin’s last specials in which he expresses his opinion on hero worship and in particular on Lance Armstrong, Tiger Woods, and Dr. Phil.

The next test is to determine if the song “Bike” by Pink Floyd was written in a drug free state. In case you can’t make them out the lyrics begin:

I’ve got a bike
You can ride it if you like
It’s got a basket
A bell that rings
And things to make it look good
I’d give it to you if I could
But I borrowed it

Available video of Pink Floyd’s Bike (blocked currently at Youtube)

and if Pink Floyd is just not your cup of tea. Here is Queen performing their song “Bicycle Race”