CYSTIC FIBROSIS (CF)
DNA ANALYSIS
Also see: 6370 - Cystic Fibrosis (CF) - CFTR Sequencing

Cystic Fibrosis (CF) is the most common autosomal recessive genetic disease with a disease frequency of approximately one in 2,500 newborns, and an estimated carrier frequency of approximately one in 25 individuals in the Caucasian and Ashkenazi Jewish populations. This disease is caused by mutations in two copies of the Cystic Fibrosis Transmembrane Regulator gene (CFTR).

Reasons for Referral:

Carrier screening
Carrier identification in persons with a family history
Confirmation of diagnosis in affected individuals
Prenatal Diagnosis
Sperm & egg donors
Abnormal fetal ultrasound

Testing Methodology:

Direct Mutation Analysis:
Our laboratory utilizes an automated high-throughput system that incorporates DNA amplification (PCR), primer extension, and allele resolution by Matrix Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) Mass Spectrometry. Our expanded CF testing panel consists of 50 mutations in the CFTR gene, which complies with and exceeds the American College of Medical Genetics/American College of Obstetrics and Gynecology recommendations for population-based carrier screening^1*.

This extended CF mutation panel includes: the 23 mutations currently recommended by the ACMG:

DF508	R553X	R117H*	1078DT	3659DC
DI507	G542X	621+1G-T	R334W	711+1G-T
G551D	N1303K	405+1G-A	R347P	1898+1G-A
W1282X	G85E	A455E	R560T	2184DA
1717-1G-A	3849+10kbC-T	3120+1G-A	R1162X	2789+5A
Plus:
Q493X	G330X	3199del6	394delTT	405+3A-C
V520	E60X	R347H	G178R	R117C*
R352Q	3849+4-G	S549N	3905insT	K710X
D1152H	Y122X	S549R	G314E	F316L
A559T	3876DA	3120G-A	G480C	2143delT

*5T variant analysis is performed as a reflex test in R117H positives (also R117C). Our MALDI-TOF MS protocol differentiates between the DF508 and the DI507 mutations, and the F508C, I507V, I506V, and I506M polymorphisms which could interfere with allele detection in other assay methods.

¹Watson MS, et al. Genet Med. 2004 Sep-Oct;6(5):387-91.

Sensitivity:

Mutation Analysis: ~ 90% detection in the Caucasian/Non-Ashkenazic population ~ 97% detection in the Ashkenazic Jewish population ~ 69% detection in the African American population ~ 57% detection in the Hispanic American population. (Detection rates according to: Richards et al., 2002. Genetics in Medicine 4: 379-391).

Specimen Requirements:

Blood: EDTA (purple-top) tubes: Adults: 10 cc; Child: 5 cc; Infant: 2-3 cc
Buccal Samples: Individual kits are provided for the collection and shipment of dried buccal samples.

Buccal Sample Collection Instructions

Blood and Buccal Collection and Shipping kits are provided free of charge to appropriate referral sources upon request (Call 1-800-411-4363). Requisition form must accompany specimen. Prior to genetic testing, we recommend genetic counseling and informed consent. Contact the laboratory directly to discuss prenatal testing.

Turnaround Time:

3 weeks

CPT Codes and Prices:

Mutation Analysis: 83788, 83914x2, 83912, 83900, 83901, 83898, 83891

Shipping Information

Forms:

>> DNA Requisition
>> Prenatal Requisition

Test Codes:

Mutation Analysis: 6014
Mutation Analysis - Prenatal: 6080