10 Facts You Need to Know about Cystic Fibrosis

Cystic fibrosis is a genetic disorder that predominantly affects the lungs and digestive system. In this article we examine the key facts on cystic fibrosis, tracing its origins and exploring treatments for this genetic disease.

1. Cystic fibrosis is the most common genetic disorder in the world.

Around 30,000 US citizens have the disorder, with approximately 1,000 new cases diagnosed every year. Unlike some genetic diseases, the condition affects males and females in equal numbers.

2. Experts attribute cystic fibrosis to a gene mutation.

All of our genes affect our bodies in different ways. Genetic anomalies are surprisingly common. They can affect the formation and function of cells to a greater or lesser extent depending on how many, and which, genes are involved in the mutation. The gene mutation that causes cystic fibrosis affects the CFTR protein, a protein that regulates the flow of saline fluids in and out of cells.

3. A classic symptom of cystic fibrosis is the body’s production of a thick, sticky mucus.

This substance can build up in the lungs, leading to damage and infection. It can also affect the digestive system and other major organs.

Secondary complications of cystic fibrosis include hepatitis, diabetes, osteoporosis and infertility.

4. Modern treatments have drastically extended the life expectancy of people with cystic fibrosis.

Cystic fibrosis was once considered a fatal childhood illness. Although the severity of symptoms can vary greatly, thanks to medical advancements, the median predicted life expectancy for a child born with cystic fibrosis in the US in 2016 was 47 years. However, some people with cystic fibrosis may live longer.

5. Cystic fibrosis is more prevalent in people of Northern European origin.

Cystic fibrosis is most prevalent in Caucasian Americans, though it is found in all ethnic groups. The advice of the American College of Obstetricians and Gynecologists is that all women should get carrier screening, regardless of family history or ethnic origin.

6. Cystic fibrosis is one of the oldest known genetic disorders in the world.

Studies have traced cystic fibrosis back some 52,000 years, to ancient man in Northern Europe. Experts believe that the gene spread throughout Europe, and beyond, as man began colonizing new areas.

7. Experts have linked the gene mutation that causes cystic fibrosis to cholera protection.

Dr Arsalan Azimi, of Shiraz University of Medical Science, Iran, recently published a paper postulating that the gene mutation responsible for cystic fibrosis could also offer other beneficial traits in terms of disease resistance. The paper suggests that people who have cystic fibrosis may be more resistant to cholera.

In evolutionary terms, cystic fibrosis may have effectively “piggybacked” on the positive genetic trait the gene mutation conferred in terms of disease resistance.

8. A person usually has to inherit two faulty gene copies to be born with cystic fibrosis.

We each inherit two copies of all of our genes: one from each parent. Generally speaking, in order to inherit cystic fibrosis, both parents must carry the associated gene mutation.

9. Some people with cystic fibrosis aren’t diagnosed until adulthood.

The mutation that causes cystic fibrosis invariably affects the CFTR protein. However, there are some 2,000 established variations of this particular anomaly. As a result, symptoms can vary greatly in severity depending which, and how many, genes are affected.

Some people exhibit milder symptoms mimicking those of other lung diseases like bronchitis or asthma. Though heel-prick tests are routine procedure for newborns in many countries today, this hasn’t always been the case. Delayed diagnosis is very rare, but it does occasionally occur.

10. People with cystic fibrosis can have their own healthy children.

To be born with cystic fibrosis, a child must usually inherit two faulty gene copies: one from each parent.

If one parent carries the mutation but does not have the disease and the other parent does not carry the gene mutation, the odds that their child will be born with cystic fibrosis are extremely low, though he or she may be a carrier of the disorder.

If both parents are carriers, there is still a 75 percent that their child will not be born with the disease. Experts estimate the likelihood of their child also being a carrier at 50 percent.

If one parent has cystic fibrosis but the other is not a carrier, it is extremely unlikely that the child will inherit the disease. However, it is a virtual certainty that all of their children will be carriers.

If one parent has cystic fibrosis and the other parent is a carrier, the odds that the child will be born with the disease are approximately 50 percent. Inheritance of at least one faulty gene is a virtual certainty.

It is for this reason that preconception genetic carrier screening plays a key role in family planning. Genetic carrier screening provides specialists with insight into the genetic makeup of the parents. This provides the knowledge necessary to provide guidance and ultimately maximize the couple’s odds of raising a healthy family.