We will be examining mutations within the cystic fibrosis transmembrane
conductance regulator gene (CFTR) that can lead to cystic fibrosis, a
common life-threatening disease. In the following lab activity, you will
visiting multiple websites to investigate and answer questions about the
disease phenotype and the mutations that lead to the disorder.
- Using a computer, visit the following websites: Online Mendelian
Inheritance in Man (OMIM) for cystic fibrosis
(https://omim.org/entry/219700), and the Wikipedia sites for the
disease and CFTR gene (https://en.wikipedia.org/wiki/Cystic_fibrosis;
https://en.wikipedia.org/wiki/Cystic_fibrosis_transmembrane_conduc
tance_regulator). There are also other links within these sites which
you may want to visit to answer the questions below. - Answer the questions below.
a. What is the function of the CFTR gene?
b. What happens when the protein from this gene becomes
dysfunctional?
c. What are major symptoms of cystic fibrosis and which organs
are affected.
d. How is the disease transmitted? (is it X-linked recessive or
other)
e. Where is the gene located, and how many exons does the CFTR
gene have?
f. How many amino acids are in the CFTR polypeptide?
g. How many different mutations within CFTR are known to lead to
cystic fibrosis? - Now that we know a bit more about the CFTR gene and cystic fibrosis,
we are going to investigate several SNPs that are associated with the
disease.
a. First, go to the website for SNPedia (https://www.snpedia.com/ )
and search for cystic fibrosis. Evaluate the information on this
website. Do genetic testing companies test for all known mutations
that are associated with cystic fibrosis?
b. We will analyze 4 different cystic fibrosis mutations
(rs113993960, rs77010898, rs80055610, rs75527207)
that are found in the dbSNP (https://www.ncbi.nlm.nih.gov/snp/ )
a. Enter the reference snp # into the dbSNP search query and
click on the link.
b. Find out where the mutation occurs, and what it does to the
gene and protein sequence.