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TMS - Where are You?
During the past decade a new method for conducting newborn screening has been developed, tested, compared, discussed, retested, praised, and sometimes even cussed. They call this technology, Tandem Mass Spectrometry, or for short, TMS. In some literature it is referred to as MSMS. You would think that by now this new technology, whatever it is called, would slowly be getting close to being part of the real world. But not in California!
A few states are well underway with their implementation of this unique and promising approach to screening newborns. Three or four years ago, the legislature of California provided the Department of Health Services with authority to purchase two sets of these spectrum analyzers. These pieces of equipment have been purchased and delivered, but the last I heard they were still gathering dust in a state warehouse somewhere.
This is occurring even after two “tandem” measures were approved by the legislature and signed by the Governor to authorize the funding to implement the use of this new technology for the newborn screening program. Yes, these monies are still not flowing. The latest “reason” for this delay is the governor has established a hiring freeze of state employees because of the energy crisis.
Because of all the foot-dragging and other types of delays, we are now having the opportunity to discuss the TMS process and its implementation in a little more detail.
Spectrometry has actually been around for a long time. At least 300 years ago, our old friend Isaac Newton recorded that he had observed white sunlight splitting into a rainbow-like spectrum after it passed through a glass prism. His notes recorded that the colors ran continuously from red to violet. Since that time, many other scientist-types have been working to develop methods for using this concept as a tool to observe and actually measure the molecules that makes up “matter”.
The TMS instrument of today is an analytical unit that can measure the weight (actually the mass) of molecules. Each molecule has a unique weight based on the type and number of atoms it contains. Things in the world are made up of different combinations of molecules – thus different weights (different mass). These weights are known and predictable.
For example, most chemistry students learn that water is made up of two-parts of Hydrogen for every one-part of Oxygen (H2O). Applying this knowledge to testing for Phenylketonuria (PKU), we can determine what to expect a single Phenylalanine molecule to weigh. We know from other science that Phenylalanine is an amino acid with a chemical formula of C6H11NO2 (Six parts of carbon, 11 parts of hydrogen, one part nitrogen, and two parts oxygen). From this we can derive the expected weight of a single Phenylalanine molecule.
In a newborn’s blood specimen, thousands of molecules are usually present ranging from very large to very small proteins. The task for the TMS analyzer is to separate and measureEACH of these molecules. It must do this at a very high rate of speed, with very good accuracy, and be able to repeat the test many times and get the same results each time. The instrument must be able to select exactly the specific molecule, and be able to know when there are variations within those select molecules. Of course, it has to beat out the competition methods.
It appears that TMS has passed all of these previously stated requirements, especially speed, and accuracy. These two capabilities drive costs, but still??? Perhaps we are overloaded with “old school” thinking. Which of those senior thoughts might that be?
As I understand the impact of this new improved technology, replacing what is currently being performed would result in each test being accomplished faster, and would require less preparation prior to running a test on a newborn’s blood. The test can be performed more accurately (resulting in fewer repeats or erroneous results), and can be done in parallel with many other tests. This should result in a major cost reduction per disorder detected).
The objections that people voice when discussing the expansion and improvement of the newborn screening program seem to be: 1) There are no national standards for what disorders are to be tested within the existing newborn screening programs. 2) Many of the proposed additional tests are for conditions occurring too rarely to be cost beneficial. 3) Many of the proposed additional tests are for conditions that are not treatable. This observer does not agree with any of their points.
No national standards — newborn screening has been occurring in some form since the late 1960s and we have not ever tried to get national agreement on what tests to conduct. So why now.
Not cost beneficial — As a test engineer during the my working career of over 35 years, I can not accept that the opinion that TMS will cost more than the existing chemical approach. The current approach is very labor intensive. A lot of tests have to be repeated. The current methods are much less efficient than the use of TMS. The TMS spectrum analyzer approach will allow for many additional disorders to be detected at a lower total cost — if they want it to.
Disorder is not currently treatable — In my opinion, it is difficult to develop solutions to problems which have yet to be identified. How do you know what to work on if you do not have knowledge about the outcome of a disorder. The results of testing newborns should lead to new treatments being developed because of increase correlation of cause and effect. What comes first?
Other scientific writers are also very positive about this new TMS technology. I am interpreting their collective writings to be saying that TMS is better, is certainly more accurate, and is a faster, more timely way of doing newborn screening tests. Their consensus is that this new TMS system will be able to test at least 30 or more disorders of faulty metabolisms, or mal-performing amino acids with no or little additional cost to the current newborn test programs. So, let’s get started!
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