CHROMOSOME NO 7

CFTR: The Gene Associated with Cystic Fibrosis | Approximate gene location is based on Chromosome 7 map from NCBI Entrez Map Viewer. |
Official Gene Symbol: CFTR
Name of Gene Product: cystic fibrosis transmembrane conductance regulator
Locus: 7q31.2 - The CFTR gene is found in region q31.2 on the long (q) arm of human chromosome 7.
Gene Structure: The normal allelic variant for this gene is about 250,000 base pairs (bp) long and contains 27 exons. mRNA: The intron-free mRNA transcript for the CFTR gene is 6129 bp long. See the NCBI sequence record NM_000492 to access the mRNA sequence data.
Coding Sequence (CDS): 4443 bp within the mRNA code for the amino acid sequence of the gene's protein product.
Protein Size: The CFTR protein is 1480 amino acids long and has a molecular weight of 168,173 Da. See the annotated CFTR protein sequence record in Swiss-Prot.
Protein Function: The normal CFTR protein product is a chloride channel protein found in membranes of cells that line passageways of the lungs, liver, pancreas, intestines, reproductive tract, and skin. CFTR is also involved in the regulation of other transport pathways.
Associated Disorders: Defective versions of this protein, caused by CFTR gene mutations, can lead to the development of cystic fibrosis (CF) and congenital bilateral aplasia of the vas deferens (CBAVD).

| Figure 1: Diagram depicting the five domains of the CFTR membrane protein (Sheppard 1999). |
Protein Structure
CFTR is a type of protein classified as an ABC (ATP-binding cassette) transporter or traffic ATPase. These proteins transport molecules such as sugars, peptides, inorganic phosphate, chloride, and metal cations across the cellular membrane. CFTR transports chloride ions (Cl-) ions across the membranes of cells in the lungs, liver, pancreas, digestive tract, reproductive tract, and skin.
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