Berkeley Fial
Michaela McNiff
 Someone gets Cystic Fibrosis when they inherit two mutated
genes – one from each parent.
 The CF gene is on chromosome 7. The parents of a child with
CF sometimes don’t have CF because they don’t have two
mutated copies of the CF gene.
 Since you need two mutated genes to get this disease it is a
recessive disorder.

Cystic Fibrosis is an autosomal recessive disease. This is a
non-sex linked disease. It is a hereditary disease. “CF is caused
by a mutation in the gene, cystic fibrosis transmembrane
conductance regulator (CFTR). The product of this gene is a
chloride ion channel important in creating sweat, digestive
juices, and mucus. Although most people without CF have two
working copies (alleles) of the CFTR gene, only one is needed to
prevent cystic fibrosis. CF develops when neither allele can
produce a functional CFTR protein.” – Wikipedia
 C - don’t have CF
c - has CF
 Cc is a possible genotype for
the parents because they
don’t have CF but carry one
of the recessive CF genes - c.
 There a 25% chance that
their child will have CF and
a 75% chance that they will
not have CF.
C
c
C
CC
Cc
c
Cc
cc
 “Cystic fibrosis is one of the
most common lifeshortening genetic diseases.
In the United States, 1 in
4,000 children is born with
CF. It is most common
among western European
populations; one in twentytwo people of Mediterranean
descent is a carrier of one
gene for CF, making it the
most common genetic
disease in these
populations.”- Wikipedia

“The CFTR gene is found at the
q31.2 locus of chromosome 7, is
230,000 base pairs long, and
creates a protein that is 1,480
amino acids long. The most
common mutation, ΔF508 is a
deletion (Δ) of three nucleotides
that results in a loss of the
amino acid phenylalanine (F) at
the 508th (508) position on the
protein. There are several
mechanisms by which these
mutations cause problems with
the CFTR protein. ΔF508, for
instance, creates a protein that
does not fold normally and is
degraded by the cell.” -Wikipedia
 If someone with CF has kids there are only 3 possible
scenarios to see if their kid will have CF.
 If one parent has CF their genotype would have to be cc, so
they could marry some one with a genotype of CC, Cc or cc.
 In the case of cc x CC there is no chance that their children
will have CF because you need a chromosome from both your
parent to get CF.
 In the case of cc x Cc there is 50% chance that their children
will have CF.
 Lastly with two parents with the genotypes cc there is a 100%
chance that their kids will have CF because both the parents
must pass on a c.

There are three different methods of diagnosing cystic fibrosis. These methods are prenatal
screening,

Prenatal Screening “If that parent is found to be a carrier of a CFTR gene mutation, the other
parent is then tested to calculate the risk that their children will have CF. Testing analyzes the
blood for the most common mutations such as ΔF508 — most commercially available tests look
for 32 or fewer different mutations. If a family has a known uncommon mutation, specific
screening for that mutation can be performed. Because not all known mutations are found on
current tests, a negative screen does not guarantee that a child will not have CF.” – Wikipedia

Sweat Test “Cystic fibrosis occurs when there is a mutation in the CFTR gene. The protein
created by this gene is anchored to the outer membrane of cells in the sweat glands, lungs,
pancreas, and other affected organs. The protein spans this membrane and acts as a channel
connecting the inner part of the cell (cytoplasm) to the surrounding fluid. In the airway this
channel is primarily responsible for controlling the movement of chloride from inside to outside
of the cell, however in the sweat ducts it facilitates the movement of chloride from the sweat into
the cytoplasm. When the CFTR protein does not work, chloride is trapped inside the cells in the
airway and outside in the skin. Because chloride is negatively charged, positively charged ions
cross into the cell because they are affected by the electrical attraction of the chloride ions.
Sodium is the most common ion in the extracellular space and the combination of sodium and
chloride creates the salt, which is lost in high amounts in the sweat of individuals with CF. This
lost salt forms the basis for the sweat test”

Genetic- By extracting DNA, scientists can read strands of DNA. Certain letter sequences
symbolize a gene characteristic for a certain gene. Through this method it is easy to determine if
the parent or child have or will have the disease.
 The disease is sometimes obvious right after birth, but some cases of CF
(Cystic Fibrosis) aren’t detected for months.
 Symptoms include:
 Pneumonia (frequently)
 Chronic cough w/ thick mucus
 Poor growth
 Abdominal swelling
 Vomiting
 Dehydration
 Malnutrition
 Poor appetite
 Difficulty breathing
 The lifespan of someone with
CF is usually between 28
and 30 years of age. The
cause of death is usually
respiratory tract infections
or respiratory distress, along
with enlargement of the right
side of the heart.
 There is no cure yet for CF.
 There are treatments for the
symptoms and diseases that
come with CF such as
treatment for lung and
digestive problems.
 Sometimes lung transplants
are made in order to give the
patient a new lung with out
the infected bacteria with in it.
 Gene therapy is being used to
try and find a cure for the
disease.
 Gene therapy is being done
to find a cure for cystic
fibrosis.
 It looks promising, but they
aren’t sure how long it will
take to actually find a cure.
 Most patients with cystic fibrosis are diagnosed by age two.
Common characteristics of this disease are “very salty-tasting
skin; persistent coughing, at times with phlegm; frequent lung
infections; wheezing or shortness of breath; poor
growth/weight gain in spite of a good appetite; and frequent
greasy, bulky stools or difficulty in bowel movements.” –
www.cff.org People who carry this disease live into their midforties, on average. This number has increased over the years
with the help of technology and medical advances. However,
this is still extremely young. Many people still die very young
 People who have cystic fibrosis are challenged to live a
“normal” life. Because of all the symptoms, the patients cannot
compete in sports and always need to have extra attention
regarding food and health concerns in general.
 The Cystic Fibrosis
Foundation is an
organization with a website
with all the information you
need to know about CF.
 This is extremely helpful for
people with family members
that have this diseases to
find more information.
 http://www.cff.org/
 Also, Cystic Fibrosis Worldwide is an organization
that’s goal is to improve the quality of life and the life
expectancy of people with CF.
 This organization reaches out to other countries by
trying to find a treatment and cure for this disease.
 http://www.cfww.org/about