Cystic fibrosis carrier screening in a North American population

Genet Med. 2014 Jul;16(7):539-46. doi: 10.1038/gim.2013.188. Epub 2013 Dec 19.

Abstract

Purpose: The aim of this study was to compare the mutation frequency distribution for a 32-mutation panel and a 69-mutation panel used for cystic fibrosis carrier screening. Further aims of the study were to examine the race-specific detection rates provided by both panels and to assess the performance of extended panels in large-scale, population-based cystic fibrosis carrier screening. Although genetic screening for the most common CFTR mutations allows detection of nearly 90% of cystic fibrosis carriers, the large number of other mutations, and their distribution within different ethnic groups, limits the utility of general population screening.

Methods: Patients referred for cystic fibrosis screening from January 2005 through December 2010 were tested using either a 32-mutation panel (n = 1,601,308 individuals) or a 69-mutation panel (n = 109,830).

Results: The carrier frequencies observed for the 69-mutation panel study population (1/36) and Caucasian (1/27) and African-American individuals (1/79) agree well with published cystic fibrosis carrier frequencies; however, a higher carrier frequency was observed for Hispanic-American individuals (1/48) using the 69-mutation panel as compared with the 32-mutation panel (1/69). The 69-mutation panel detected ~20% more mutations than the 32-mutation panel for both African-American and Hispanic-American individuals.

Conclusion: Expanded panels using race-specific variants can improve cystic fibrosis carrier detection rates within specific populations. However, it is important that the pathogenicity and the relative frequency of these variants are confirmed.

MeSH terms

  • African Americans / statistics & numerical data*
  • Cystic Fibrosis / diagnosis*
  • Cystic Fibrosis / epidemiology
  • Cystic Fibrosis / genetics
  • Cystic Fibrosis Transmembrane Conductance Regulator / genetics*
  • European Continental Ancestry Group / statistics & numerical data*
  • Gene Frequency
  • Genetic Carrier Screening*
  • Genetic Testing*
  • Hispanic Americans / statistics & numerical data*
  • Humans
  • Mutation / genetics*
  • United States / epidemiology

Substances

  • CFTR protein, human
  • Cystic Fibrosis Transmembrane Conductance Regulator