Cystic Fibrosis (CF) Profile, DNA Analysis and 5T Allele Genotyping

Whole blood or LabCorp buccal swab kit (buccal swab collection kit contains instructions for use of a buccal swab)

7 mL whole blood or LabCorp buccal swab kit

3 mL whole blood or two buccal swabs

Lavender-top (EDTA) tube or LabCorp buccal swab kit

Determine affected or carrier status for the 32 most common CF mutations (includes the mutation panel currently recommended by the ACMG and the ACOG); determine the presence of the 5T allele

This assay detects as many as 90% of cystic fibrosis carriers in the Caucasian population. Within other ethnic groups, there may be higher or lower detection efficiency. Routine screening for the 5T allele in the cystic fibrosis (CF) gene as part of standard CF carrier screening is not recommended, since the goal of carrier screening is to identify couples at risk for having children with cystic fibrosis. The 5T allele is associated primarily with male infertility or atypical symptoms, although many individuals are asymptomatic.

Analysis of the 5T allele may be a useful adjunct to the standard CF panel of 32 mutations in patients with male infertility or idiopathic pancreatitis. Genetic counseling is recommended for any person testing positive for the 5T variant.

Polymerase chain reaction (PCR) and a solution-phase multiplex allele-specific primer extension with subsequent hybridization to a bead array followed by fluorescence detection.

Cystic fibrosis (OMIM 602421) is a common genetic disorder resulting in chronic pulmonary and gastrointestinal/pancreatic disease. There is wide variability in clinical symptoms. CF is inherited in a recessive manner, which means that both parents must be carriers to have an affected child. When both parents are carriers, there is a 25% chance with each pregnancy that the child will be affected. Genetic counseling and CF molecular testing are recommended for the reproductive partners and at-risk family members of CF carriers.

LabCorp also offers Cystic Fibrosis (CF) Profile, 97 Mutations, CF plus® [450020] for 97 CF-causing mutations, which has specific utility for partners of known carriers, equivocal/diagnostic cases, high-risk couples (previous affected child) for whom at least one mutation remains unidentified after ACMG/ACOG profile testing, or for those persons whose ethnicity requires testing for less common mutations.