The Molecular Nature And The Inheritance Pattern Of The Disease / Disorder

CF happens because two parents have a defect in the CF transmembrane conductor regulator (CFTR) gene. If a child has only one parent that has a

Cystic Fibrosis (CF) is a genetic disorder in which mucus glands produce abnormally thick secretions. These secretions can lead to chronic infections of the lungs and eventually lead to obstruction of the pancreas, resulting in digestive enzyme deficiency, the liver is also sometimes affected. Secretions from the sweat and salivary glands of a CF patient frequently contain abnormally high amounts of sodium and chloride. Because the body produces a high amount of salt, a sweat test is generally used to diagnose the disorder.

Cystic fibrosis is a genetic disease that is programmed in the victim’s DNA. It is passed on from parents who are both carriers of the defective gene. This genetic disorder affects the respiratory and digestive systems. People who suffer from cystic fibrosis usually inherit a defective gene on chromosome 7 called CFTR (cystic fibrosis transmembrane conductance regulator). Below is a diagram showing how cystic fibrosis is passed on from carrier parents to a child. The diagram shows that when a child is born by two parents who are both carriers of the CFTR defective gene, there is a one in four chance of being born with cystic fibrosis, there is a 2 in 4 chance of being a carrier or a 1 in

A defect in the CFTR gene, or cystic fibrosis transmembrane regulator gene, is what causes Cystic Fibrosis. Every person inherits two of these genes, one coming from each parent. If a child inherits a faulty CFTR gene from both parents they will have CF. If a child inherits only one faulty CFTR gene, they are considered “CF carriers” ("What Causes Cystic Fibrosis?," 2013). More than 10 million Americans are carriers of the defective CF gene ("Cystic Fibrosis Foundation – Testing for Cystic Fibrosis," 2014). Carriers are able to live a normal, healthy life and they usually have no symptoms of CF, however, they could pass the faulty CFTR gene down to their children ("What Causes Cystic Fibrosis?," 2013). Carrier testing is available to help people identify if they could pass down the gene. The test uses blood samples or scraped cells from inside the cheek to look at a person’s genetic material ("Cystic Fibrosis Foundation – Testing for Cystic Fibrosis," 2014). The figure below shows how the CFTR gene can be inherited (Kotrla, 2014).

Like the world around us the medical field is always changing. It is always pushing forward, trying to understand mysteries of the human body that have boggled researchers for decades. What confuses scientists more, are the organisms or conditions that create these abnormalities that can send the human body into a downward spiral. Disease is something that has affected human civilization since the dawn of time. It can either be chronic or acute, but in either case it has the potential to bring havoc to the human body systems that can lead to devastating consequences. Generally there are two main types of diseases, ones caused by invading pathogens and those which are hereditary. One hereditary disease that can be particularly tragic is

There are two types of diseases, infectious and genetic. Unlike infectious diseases that are caused by organisms such as bacteria, genetic disorders are caused by mutations in an organism’s DNA. Cystic Fibrosis is a genetic disorder that is recessive autosomal and causes the creation of thick and sticky mucus. Because the disorder is recessive there must be two recessive alleles present for the trait to be expressed. Whereas in dominant disorders only one dominant allele needs to be present to express a disorder. For there to be two recessive alleles, both of the parents must be homozygous recessive or heterozygous for the offspring to express the recessive trait. If the offspring is heterozygous they will become carriers of the disorder and

Cystic Fibrosis is a genetic disorder caused by a mutation in a gene called the cystic fibrosis transmembrane conductance regulator (CFTR). The inheritance pattern is autosomal recessive. This means, to have symptoms of CF, you must have two defective CFTR genes, by inheriting a mutant copy of the CFTR gene from both your mother and your father. If you inherit a single defective CFTR gene from either your mother or your father, you are a “carrier” of the disease, but do not show symptoms, since it is a recessive gene. However, you could pass the gene onto your child and they could end up having cystic fibrosis, even if you do not have it. The CFTR gene makes a protein that controls how much salt and water move in and out of the body’s cells.

What type of mutation is it? People who have cystic fibrosis have a faulty gene on chromosome 7, this is called CFTR which stands for cystic fibrosis transmembrane conductance regulator. The protein that is produced by this gene usually helps salts (sodium chloride) move in and out of cells, but if the protein doesn’t work like it is suppose to, the movement is blocked and an abnormal thick mucus is produced on the outside of the cell. The cells which are mostly affected are the lung cells.

Cystic Fibrosis (CF) is a disease that causes problems within the lungs and digestive systems (pancreas, livers, and intestines). It occurs due to the abnormal transport of chloride and sodium across an epithelium, leading to excessive secretion of thick mucus in these two major areas of the body. This makes breathing difficult as the thick, sticky mucus clogs the airway, and it can also result in sinus infections, poor growth, infertility, and reduced life expectancy. However, these can sometimes be treated with antibiotics and other medication, like medicated inhalers.’ It is an autosomal recessive genetic disorder and is caused by one of many different mutations in the gene for the protein cystic fibrosis transmembrane conductance regulator (CFTR)’ . Because CF is a genetic disorder it is able to be inherited therefore can undergo human manipulations such as Selective Breeding and Gene Therapy.

In patients with CF, dysregulation of sodium and chloride ions transport may lead to multiple organ damage. Depending on the type of gene mutation of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene, the patient may have various clinical

Cystic Fibrosis (CF) is an autosomal recessive gene that causes a wide range of symptoms because there are over 1,000 changes or mutations that can occur within the cystic fibrosis transmembrane receptor (CFTR) protein. The CFTR protein is generally a chloride ion chain “regulated by cyclic adenosine monophosphate and therefore can act as a regulator of other electrolyte channels”(Grossman, S., & Grossman, L. 2005, p. 46). Typically this protein allows chloride ions to exit mucus-producing cells allowing water to flow in and thin the mucus. However, if the CFTR protein has been mutated, such as in cystic fibrosis, chloride ions cannot exit. This causes the mucus to thicken, become sticky, and obstruct the various channels it passes through. This build up of mucus also prevents bacteria from being cleaned from cells thoroughly increasing the patients risk for infections (Grossman, S., & Grossman, L. 2005). However, the severity of CF depends on whether the patients have complete or partial loss of the CFTR gene. If the person has the classic form of CF abnormalities of CFTR will commonly affect “…the respiratory, gastrointestinal, endocrine and metabolic, and genitourinary systems”(Schram, C. 2012). However, if people have atypical forms of CF their genetic disorder may only affect one of the organ systems and may not be found until the patient develops symptoms in their late childhood, early adolescence, or adulthood

Cystic fibrosis is a progressive, debilitating, inherited autosomal recessive disorder caused by a mutation to chromosome 7 this is required for producing the transmembrane conductance regulator (CFTR) responsible for regulating the sodium and chloride levels within a cell. (NHS, 2015) If the CFTR gene is defective or absent it creates an imbalance resulting in an accumulation of mucus leading to organ damage primarily

Cystic Fibrosis is caused by a genetic defect in Chromosome 7. Chromosome 7 encodes the cystic fibrosis transmembrane conductance regulator, also known as CFTR. There are over 1,000 mutations of this gene causing cystic fibrosis, with each mutation manifesting as a different variation of disease onset and clinical presentation. The most common mutation is the loss of phenylalanine residue at deltaF508. The abnormal functioning CFTR causes impaired chloride transport and more viscous secretions. The defect causes dehydrated secretions in the respiratory tract and gastrointestinal tract. Being dehydrated, these secretions become more difficult to move throughout the body. Along with impaired

conductance regulator is the dysfunctional gene responsible for CF. The gene can be found on human chromosome 7, and is responsible for the synthesis of a specific protein by the same name (cystic fibrosis transmembrane conductance regulator). CFTR is an important protein responsible for the transportation of sodium and chloride ions (NaCl) in and out of mucus producing cells that are found in epithelia of sweat glands, lungs, gastrointestinal tract, pancreas and vas deferens (Schechter, 2014, p. 21). Cystic fibrosis is primarily an exocrine disorder affecting glandular secretions that function to maintain homeostasis via the sweat glands and respiratory, digestive, and reproductive tracts (Cystic, n.d.).

A point mutation occurs when one nucleotide is deleted. For point mutations, an entire base pair can be deleted or a base from the master strand can be missing. This deletion can create a frame shift in certain cases. A frame shift can shift the way that DNA is read. A chromosome deletion occurs when a whole section is chrome is deleted. To qualify as a chromosome deletion more than one base pair has to be deleted or it would be considered a point deletion. Cystic Fibrosis is caused by a point deletion. The CFTR gene is made up of 250,000 DNA nucleotides and is found on human chromosome 7. The CFTR protein works as a channel for chloride ions that move in and out of the cell. This helps maintain the balance between salt and water. CFTR is short of Cystic Fibrosis Transmembrane Conductance Regulator. A change in the CFTR gene can negatively affect the CFTR protein. The deletion of three DNA nucleotides can cause a CFTR mutation. When the three DNA nucleotides are delete the amino acid Phenylalanine is deleted. Phenylalanine is located at position 508 in a protein sequence. This results in the build up of mucus in many parts of the body. Cystic Fibrosis (CF) can affect a patient’s respiratory, reproductive and