Non-classical PKU: Hyperphenylalaninemia

In talking to my family and friends I can see that there is a lot of things that people don't understand about this genetic disorder. So here it is. All you need and want to know about Hyperphenylalaninemia (except how to pronounce it!)

What is Hyperphenylalaninemia?

An inherited condition in which a person's body is unable to properly utilize one part of protein found in food. This condition causes mildly increased levels of phenylalanine in the blood.

To understand why the phenylalanine is increased in the blood of a person with Hyperphe, we need to explain how the body handles proteins found in foods. Proteins are made up of amino acids fastened in a chain.

One of these amino acids is called phenylalanine. The body takes food protein, digests it into amino acids, and then uses the amino acids to make all organs and tissues in the body. The process is as follows: when protein is eaten, it is broken into the individual amino acids. The amino acids are then absorbed from the intestinal tract into the blood stream and carried around the body to where they are needed to build body proteins. The amino acids remaining after sufficient protein has been formed are broken down into harmless waste products. With Hyperphe, the leftover phenylalanine is not broken down. This causes increased blood levels of phenylalanine.

How did they get it?

Everyone has two #12 chromosomes. Each of the #12 chromosomes has one site for the PKU gene. A carrier of PKU has a mutation on one of the #12 chromosomes. If a carrier (me) marries another carrier (John) who also has a mutation on the #12 chromosome, there is a one in four chance at each pregnancy that their child will inherit two mutant PKU genes, one from each parent. As soon as a child with PKU is born, you automatically know that both parents have a mutation that the child inherited. This also means one of both John and my parents also have to be carriers. Our siblings and nieces and nephews can be carriers also. It will only effect the offspring of two carriers who have both passed their bad gene.

How many people have it?

1 in 10,000

How did they get non-classical PKU vs PKU?

John or I have a mutated mutation. One of us passed a normal PKU mutation on our #12 chromosome. The other passed a mutated PKU mutation on our #12 chromosome.

Will they pass it to their children?

Only if they marry someone who is a carrier for PKU. Both #12 genes have to have the mutation. That is why John and I had no idea we were carriers. We only carry 1 bad gene. Caleb can be a carrier and can also pass it on if he has inherited one of our genes and marries a carrier. He inherited at least one normal gene from John or I because he does not have the condition. He could have inherited both of our good genes too.

Is there any cure?

Just a restricted diet. Compared to the other genetic disorders out there we are very blessed!

When do they treat Hyperphe:

Because the condition is so rare it varies from State to State and Dr to Dr. These are general guidelines.

Standards Used by the Texas Department of State Health Services Quantitative PHE by Fluorometric Analysis
Blood Level of PHE		Diagnosis	Treatment
(mg/dL)	Micromoles/Liter
<>	<>	Normal	None
4 - 10	240-600	Mild Hyperphe	A low PHE diet is usually not prescribed during childhood. A low PHE diet may be needed during pregnancy.
10.1 - 19.9	606-1194	Atypical PKU	Requires a low PHE diet. Women must have a low PHE diet before and during pregnancy.
20 and higher	1200 or higher	Classical PKU	A low PHE diet is needed to prevent mental retardation. Women must have a low PHE diet before and during pregnancy.

Where are your kids levels?

Davis is doing good at 209. 1 year ago he was at 271. He will be tested again in 3 months.

Beckhams numbers have risen dramatically in 6 months from 184 to 329. We are redoing a second test on Monday or Tuesday to see where his PHE number is at that time. If it is still over 300 he will start to be what is called, "on diet." This means that they will start to replace some of his milk with a protein formula that does not have phenylalanine in it.

Why does your Dr want to cut all major protein from your kids diet?

The biggest reason is to keep them off diet. The blood levels that are taken are primarily a matter of how much their body cant process and how much protein they are eating. If they are drinking a lot of milk and eating a lot of cheese their numbers will go up. If they have any kind of aspartame their numbers will jump significantly since aspartame is 50% phenylalanine.

It is imperative that we keep their numbers low for factors that are out of our control such as illness. When they are sick their numbers can jump significantly since the body burns muscle in sickness to add extra calories for your body to fight an illness off. Muscle is pure protein.

They also want them to develop a taste palate while they are young that does not include high protein foods so that later in life they will naturally control their numbers and not feel like they are sacrificing.

We also wont have to be so strict with counting protein if we eliminate the major proteins that will increase their numbers over time. We can basically let them splurge on holidays or while at Disneyland since we know we are keeping their numbers low as a baseline.

It is proven research that the lower their numbers over time the better off. Higher levels of phenylalanine in the blood cause: aggression, depression, concentration problems, ADHD, and can eventually lead to mental retardation. Our boys levels are such that they will probably never become mentally retarded because of their levels. But their levels if left unchecked can easily cause depression, aggression, and problems learning in school.

At what PHE Number do the aggression, depression, concentration problems, and ADHD start?

There is no set number. For sure you don't want their levels to get up to 600. For any permanent damage to be done it would have to be elevated levels for an extended period of time. It seems that 300 or 360 is around the standard level where they are put on diet.

Wont that effect their growth to have so little protein?

Beckham needs 12 grams of protein a day to grow "normally." That is equal to 1 1/2 cups of milk.

Davis needs 15 grams of protein a day to grown "normally." That is equal to 2 cups of milk a day.

Protein is in so much of what you eat you don't even notice. For example popcorn has 4 grams, breadcrumbs have 4 grams, pasta noddles have 8, a cup of milk has 8.

Why don't you just use soy or tofu?

Still protein...but I thought the same thing too :)

How are you going to still get them healthy calories and not just fill them up on empty sugar and carbs?

I have no idea. Any suggestions send them my way! I just dropped $200 at Costco on any snacks I could find that had 1 gram of protein or less. Its was my kids favorite day at Costco ever! Crackers, fruit snacks, dehydrated fruit, pudding cups, applesauce, fruit cups. I felt so guilty and I swear every person we passed looked at my cart and thought I was an irresponsible mom.

Why are you such a control freak?

I cant help it, its genetic. We just don't know what chromosome its passed on yet :)