title: Comprehensive genetic analysis of the cystic fibrosis transmembrane conductance regulator from dried blood specimens--implications for newborn screening.
abstract: OBJECTIVE
  In the United States, approximately 1/3,700 babies is born with cystic fibrosis each year. The >1,300 documented sequence variants pose a challenge for detection of cystic fibrosis through genetic screening. To investigate whether comprehensive characterization of the cystic fibrosis gene is feasible using dried newborn blood specimens, we modified the whole blood Ambry Test: CF and determined its sensitivity by testing DNA from individuals with cystic fibrosis who still had unknown mutations after commercial mutation panel testing.
  
  
  METHODS
  DNA from 42 archived newborn dried blood specimens of affected Hispanic, African-American and Caucasian individuals in California was analyzed by temporal temperature gradient electrophoresis screening and targeted sequencing, and by gross deletion analysis.
  
  
  RESULTS
  Excluding two specimens that could not be analyzed due to poor DNA quality, we report a 100% sensitivity and clinical detection rate in the remaining 40 patients. Eighty-three mutations representing 40 different variants were detected, including 8 novel mutations.
  
  
  CONCLUSIONS
  This study demonstrates the feasibility of temporal temperature gradient electrophoresis-based full sequence analysis and targeted sequencing from DNA in newborn blood specimens. The Ambry Test: CF, as an additional step in cystic fibrosis newborn screening models, can be used to dramatically reduce the number of cystic fibrosis carrier sweat test referrals.
authors.affiliation: Ambry Genetics, 100 Columbia #200, Aliso Viejo, CA 92656, USA.
authors.forename: Anja
authors.initials: A
authors.lastname: Kammesheidt
authors.forename: Martin
authors.initials: M
authors.lastname: Kharrazi
authors.forename: Steve
authors.initials: S
authors.lastname: Graham
authors.forename: Suzanne
authors.initials: S
authors.lastname: Young
authors.forename: Michelle
authors.initials: M
authors.lastname: Pearl
authors.forename: Charles
authors.initials: C
authors.lastname: Dunlop
authors.forename: Steven
authors.initials: S
authors.lastname: Keiles
mesh_terms: D001800:Blood Specimen Collection; D003550:Cystic Fibrosis / Q000097:blood / Q000175:diagnosis* / Q000235:genetics*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D004247:DNA / Q000097:blood / Q000235:genetics; D004252:DNA Mutational Analysis / Q000379:methods / Q000706:statistics & numerical data; D005820:Genetic Testing / Q000379:methods / Q000706:statistics & numerical data; D006801:Humans; D007231:Infant, Newborn; D015997:Neonatal Screening / Q000379:methods; D012680:Sensitivity and Specificity
chemical_list: C505032:CFTR protein, human; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D004247:DNA