B12 Breakthrough: Patient #1

B12 Breakthrough: Patient #1

CREATED Nov 21, 2013

AURORA, Colo. (Ivanhoe Newswire) – A recent discovery identified a rare genetic defect for the first time ever.

Ten-year-old Max plays the keyboard with his head, the drum with his foot, and communicates by computer with his elbows.

"He's amazing because through all these challenges he's still so smart," Abbey Watson, Max's Sister, told Ivanhoe.

It took nearly ten years after max was born for doctors at the University of Colorado School of Medicine to identify the cause of his disease.

He is the first of 14 boys to be diagnosed with Cobalamin-X, a rare disease in which his cells cannot properly process vitamin B12—leading to a buildup of toxins in the body.

"We were told he was one of 250 in the world when he was four months old," Deana Watson told Ivanhoe.

Eventually 13 others were identified, but Max's symptoms were more severe than the others.   Doctors were stymied.

Using blood samples from Max and his parents, researchers sequenced millions of tiny pieces of DNA, every gene, and discovered a mutation on Max's X chromosome.

"Low and behold, we sequence this same gene in which we found a flaw in Max. The other 13 boys had flaws in that same gene. That was the ‘ah-ha' moment," Tamim H. Shaikh, PhD, Associate Professor of Pediatrics, University of Colorado School of Medicine, told Ivanhoe.

"All parents wonder what impact their child is going to have on the world and Max has altered medical history," Steve Watson, Max's dad, told Ivanhoe.

The findings, while important to science, do not change things for Max.  The hope is that one day doctors will be able to predict and maybe even prevent such birth defects by sequencing the entire human genome of parents in advance.


BACKGROUND: Vitamin B12 is a supplement that works to support healthy nerve and blood cells. This nutrient also aids in prevention of megaloblastic anemia that causes people to feel weak and tired. Vitamin B12 is found in foods such as clams, beef liver, eggs, milk, poultry, meat, and fish, but many individuals decide to take an added dose of B12 to support a fast metabolism and gain an increase of energy. The B12 nutrient also counters dementia, improves athletic performance, and heart disease and has not shown any signs of harmful effects. (Source: http://ods.od.nih.gov/factsheets/VitaminB12-QuickFacts/)    

SYMPTOMS OF VITAMIN B12 DEFICIENCY: If a person is to have a vitamin B12 deficiency, it can mean a number of different things. Though it is extremely rare for a person to have a low count of B12, it is seen more in the elderly, HIV-infected individuals, and vegetarians. Symptoms of vitamin B12 deficiency include:

•  Difficulty walking

•  Memory loss, dementia and disorientation

•  Tingling or numbness in toes and fingers

•  Depression or mood changes (Source: http://www.webmd.com/food-recipes/guide/vitamin-b12-deficiency-symptoms-causes)

BIRTH DEFECTS: Pregnant women who are vitamin B12 deficient run the risk of giving birth to a baby with birth defects. A study shows that B12 deficiency in early pregnancy increased the risk for delivering a baby with a birth defect up to five times. Spina bifida is a common birth defect to babies who are born with a deficiency of vitamin B12. Women who are pregnant are advised to eat foods that are rich in vitamin B12 or take supplements that will provide them with the nourishment they need to reduce the risk of birth defects. (Source: http://www.webmd.com/baby/news/20090302/birth-defects-linked-to-low-vitamin-b12)  

SPINA BIFIDA: Spina bifida, meaning split spine is the most common birth defect caused by a vitamin B12 deficiency. This occurs when the baby is in the womb and the spinal cord does not close all of the way. This defect may cause paralysis and anencephaly which is a fatal condition that includes underdevelopment in the brain and the skull. To treat the defect, surgery is performed two to three days after surgery. To prevent any defects, folic acid, and B12 consumption are strongly recommended.  (Source: http://www.webmd.com/baby/news/20090302/birth-defects-linked-to-low-vitamin-b12 andhttp://www.spinabifidaassociation.org/site/c.evKRI7OXIoJ8H/b.8277225/k.5A79/What_is_Spina_Bifida.htm)


Tamim Shaikh, PhD, Associate Professor of Pediatrics, University of Colorado School of Medicine, talks about a new disease called Cobalamin X.

What's new about your discovery?

Dr. Shaikh: Max Watson, the child who we are talking about here, was the patient that was evaluated here at the Children's Hospital Colorado within a few months after birth. He had all these different symptoms; seizures and things like that. Initially, he used to have up to 200 to 250 seizures a day. They found some brain malformations which had to be corrected by surgery. However, at the same time when they looked at his test results that suggested that he had a specific type of disease called Cobalamin X., where these patients cannot process Vitamin B12 properly. Vitamin B12 is an important substance used by your body to burn fuels. If Vitamin B12 is not being processed properly, you end up accumulating bad things in your body and in your cells.

Can you tell us more about Max?

Dr. Shaikh: So, Max had many symptoms that matched that disease. When they did the test, he looked like he could have CBLC. The doctors said ‘okay if he has CBLC let's find out if he has a flaw in the gene for CBLC.' So they did an analysis when they looked at just that gene. And they look to see the entire sequence, they went through the entire gene chemically, and asked the question ‘are there any flaws in this gene that explains Max's disease?' They couldn't find any flaws. So clearly, even though his symptoms were similar to kids who have CBLC, he did not have flaws in that gene.

So then the question became where is this flaw? And that's when we came into the study. The technique that we use is actually a technique that sequences at all the genes. And that's when we first found out that he had a mutation on the specific gene on the X chromosome. As we did more work experiments we figured out that this gene actually controls the working of the enzyme that causes CBLC. So, remember I told you the gene that causes CBLC didn't have any mutations; but our gene that we found controls it.  So it's an indirect mechanism by which our mutation is now causing the exact same thing. That's what had the doctors puzzled for the longest time.

Is it a new disease?

Dr. Shaikh: It is a new completely new form of this disease. We call it CBLX. The reason why we call it CBLX is because the gene is on the X chromosome. This is important because boys only have one X chromosome, and that's where the problem arises. So that is why all the children in whom we have found this disease have been boys. This is something that is important in the future for doctors, as well as the genetic counselors who counsel families about recurrence risks, to be able to tell the parents if the mother is a carrier.

What does all of that mean for Max?

Dr. Shaikh: The problem with some of these types of diseases is that they appear in utero. He will continue to have all the problems because of what happened in utero. Because we know now that this gene is doing these particular things we can at least treat some of the symptoms. So for example his seizures can be controlled by giving him medication and we can supply the Cobalamin or the Vitamin B12 in the form that his body can now use and absorb and to remove those bad things from his system.

Can you talk a little bit about the bigger picture in terms of what it means to identify something like this down the road?

Dr. Shaikh: What our work is telling us is that there are a lot of children out there who are undiagnosed, even after having all the possible tests that are out there. We hope that right now if we were to do this on patients our chances of finding that genetic flaw went up exponentially because of the techniques that have become available in the past few years.


Dan Myers
Director of Communications and Me
University of Colorado Anschutz Medical Campus
(303) 724-7904