Unidentified Gene for Cystic Fibrosis Possible
Researchers find some with CF don't have the only known gene mutation
WEDNESDAY, Oct. 30, 2002 (HealthDayNews) -- Some people with cystic fibrosis (CF) lack any of the more than 1,000 reported disease-causing mutations in the only known CF gene, says a study by Johns Hopkins Medical Institutions researchers.
That means there may be another unidentified gene that causes CF in those people or they have another unknown disease with symptoms similar to CF, the researchers say. CF is a life-shortening disease that causes frequent, severe lung infections.
The study was presented at the recent annual meeting of the American Society for Human Genetics and appeared in a recent issue of The New England Journal of Medicine.
More than a decade ago, scientists found CF was caused by the loss of the function of a protein called CFTR. Less severe cases of CF are referred to as non-classic CF. People with non-classic CF do have some working CFTR, but not at normal levels.
This study involved detailed genetic analysis of 74 people diagnosed with non-classic CF. The results showed that 29 of the people had mutations in both copies of the CFTR gene, 15 had only a single mutation and 30 had no detectable mutations in the CFTR gene.
The findings should prompt discussion about what is and isn't non-classic CF, says Dr. Garry Cutting, director of the DNA Diagnostic Lab at the McKusick-Nathans Institute of Genetic Medicine at Hopkins.
Extensive clinical evaluation of people without identifiable changes in the CFTR gene may lead to improved diagnosis and treatment of CF and CF-like conditions, Cutting says.
To learn more, go to the Cystic Fibrosis Foundation.