Posts Tagged ‘Genetics’

Did you cause your child’s Heart Defect?

April 9, 2010

There has been some recent news coverage that contends that you just might have, if you were obese when you became pregnant.  But just in case you need to be reminded, News organizations make money by selling their product. There are lots of ways to do this, but two of them are really effective: 1) Make something so appealing that you just have to know more; and 2) Scare you so bad that you tune in/buy a copy to learn how to protect yourself.

How many Heart Moms look at their child in an ICU unit and ask themselves “What if…?” I’d wager that the answer to that question is all of them.

So you need to take health news on TV and in magazines with a grain of salt. A big grain of salt, really. The first thing I would recommend is that you drop by Gary Schwitzer’s Health News Review Blog. Gary has been in the Health Reporting field for 30 years, and he’ll tell you if the latest news report is wrong, and how it is wrong. This is a great resource to check out all those “We’re doomed!” news stories for yourself. Gary can teach you how to look at those news stories with a critical eye and not be scared to death.

Don’t take everything you read or hear at face value; if possible, try to find the original research. Read the information for yourself; then make an informed decision.

Did you cause your child’s Heart Defect? No one can tell you for sure. The new report that is stirring so much concern says that there is a better chance of having a child with a Heart Defect, but obviously it is not a certainty.

The heart begins as a straight tube, much like a drinking straw. As the heart develops it actually starts to beat in this configuration! Later, it will twist and fold over onto itself, forming a loop that will begin to grow together and form the organ that we are all familiar with.

All this happens before you even think that you might be pregnant. By the time you see the doctor to confirm it, the heart has formed. If you are destined to be a Heart Mom, it has already been decided.

Now this doesn’t mean that you can ignore all of your doctor’s advice! But think about it – millions of women have been like my mom – she did everything right, tried to follow their  doctor’s instructions to the letter, and still  I was born with a Heart Defect. Other women had every vice known to man, and their children were born healthy. So what causes Heart Defects?

I think that the main cause is a combination of genetics and environment. Research funded by the March of Dimes has found several genes that interact to help the heart form. Of special interest is the GATA4 gene – something it does helps the heart split into the left and right sides and form the Septum.  Figure out what is happening there, and maybe you can stop ASDs and VSDs!

The National Heart Lung and Blood Institute (NHLBI) has also determined that genetics play a part in the development of Hypoplastic Left Heart Syndrome (HLHS). A study of the family medical history of HLHS patients found that their ancestors also had a specific heart problem: a Bicuspid Aortic Valve. So apparently there is a genetic cause for HLHS – now the challenge is to find it.

Environment also contributes to heart defects. A section of Baltimore, Maryland contains a “cluster” where the incidence of HLHS is twice as high as the national average. What is going on there? What makes that area so different that it could trigger a Heart Defect?

Nationally, the incidence of Heart Defects is 1 out of every 125 newborns. But in the state of Wisconsin, the rate is 1 out of every 74 newborns. Wisconsin isn’t taking this lying down – they’ve created the Wisconsin Pediatric Cardiac Registry and are studying the data that it has generated, looking for clusters and what might be in the area that could create a Heart Defect hot spot.

What is the interaction between genetic factors and environment? What happens that triggers the formation of a heart defect? No one is certain, and the scary answer is that different factors contribute to different heart defects.  But if one day we could answer those questions, then maybe we could slam the door on Congenital Heart Defects.

Because every heart deserves to live a lifetime.

New studies of ToF

July 30, 2009

There is new research into the causes of Tetralogy of Fallot (ToF), focusing on the genetic makeup of ToF hearts.

“Tetralogy” means “four parts,”  and ToF is a combination of four separate problems : a Ventricular Septal Defect (VSD);  Pulmonary Stenosis; an Overriding Aorta; and an extremely muscular Right Ventricle. (Here’s a diagram)

ToF accounts for about 10% of all heart defects, and was the defect that the Blalock-Taussig Shunt was designed to relieve. The B-T Shunt was a palliative measure, meaning that instead of curing the defect, it was meant to relieve it. Even today there is no cure for Tetralogy of Fallot, although it can be surgically repaired.

ToF has always been a puzzling defect because the parents of a Tet child usually have no cardiac issues. Recent research only deepened the mystery as it seems that there is no genetic predisposition, either. ToF seems to “pop up” when it wants to.

Scientists at the Howard Hughes Medical Institute have recently found some clues into the genetic makeup of  the defect. After scouring the DNA of 114 Fallot patients, they have found 11 segments that might lead to the occurrence of Tetralogy of Fallot. They are so small that if you put all these DNA segments together, you can’t see them.

Technically these segments are known as copy number variations. The segments control how much protein is produced by a cell, and the variations can cause too much of one protein, not enough of another – and alter your health forever. So now the work shifts to identifying and controlling individual genes. One has already been found: change that gene, and the risk of having ToF multiplies by nine.

Perhaps this research will one day lead to a pill or injection for expectant mothers  that will stabilize the child’s DNA and prevent the occurance of Tetralogy of Fallot!

Link Invasion!

October 17, 2008

There are all kinds of interesting news to report to you today!

Researchers have discovered that baby mouse hearts can do this in the womb! The next step, hopefully, if figuring out how to make it happen in humans!

Rural Medicine: “Everyone needs you and you’re the only game in town.”

Better hospitals send you home more often. For your reference, here’s the 2008 quality report (PDF file). 5,000 Hospitals are rated.

Medical crisis at 30,000 feet…. You had better hope there is a doctor on board. On this plane, the first aid kit was inadequate.

The MedEx 1000 weighs less than 40 pounds and is completely portable. It’s an ICU in a Suitcase!

Here’s a real “Holy Cow!” moment: Eddie Adcock plays his banjo while undergoing brain surgery! Of course, there’s a video.

If you remember this song, you can save a life! Just remember, practice makes perfect…