They may also recognize healthy carriers of the altered gene. One of these segments must contain the altered gene. In the future, when researchers have covered all the chromosomes with overlapping fragments of DNA, any fragment they want will be available from a computer database. Finally they find the guilty gene and determine the error in its sequence of bases. The most common error in the CF gene is a deletion of three DNA bases out of a total 250,000.
Scientists can test for the disease directly in patients and prenatally.
They can study the disease process in cultured cells and in animals, with a view to developing new treatments. Knowing the gene's sequence, scientists use the genetic code to determine which amino acids make up the protein. Then they study the protein and find out what it is supposed to do. The tens of thousands of proteins in the body have different shapes and do different jobs, depending on instructions encoded in the gene. The elongated shape of a collagen protein shown in this molecular model, allows collagen to provide structural support to cells and organs.