title: [Use of buccal swab as a source of genomic DNA for genetic screening in patients with age-related macular degeneration].
abstract: OBJECTIVE
  The collection of buccal cells with swabs provides a noninvasive method for obtaining genomic DNA for genetic screening. We aimed to study the feasibility of using buccal swabs for genetic screening in patients with exudative age-related macular degeneration (AMD).
  
  
  METHODS
  Blood and buccal swabs were collected for genetic analysis from 65 patients with exudative AMD. Genomic DNA was isolated from either blood or buccal swabs. The yield of genomic DNA from both sources was determined by spectrophotometer. Genotyping for CFH, LOC387715, and HTRA1 Polymorphisms was performed using a method of polymerase chain reaction (PCR) followed by restriction enzyme digestion. Results using genomic DNA from blood or buccal swabs were compared.
  
  
  RESULTS
  Three swabs were obtained from each patient, 2 from each side of buccal mucosa, and 1 from both upper and inferior gingival mucosa. From swabs with genomic DNA extracted within a week after sample collection, an average of (3.17 ± 1.46) µg genomic DNA was obtained from swab collected from the left or right side buccal mucosa, and (3.94 ± 1.04) µg from swab collected from the upper and inferior gingival mucosa, with relatively higher yield of genomic DNA from the upper and inferior gingival mucosa (t = 6.79, P < 0.05). From swabs of the left or right side buccal mucosa after being stored at -20°C for 12 months, an average of (3.10 ± 1.17) µg genomic DNA was obtained, which showed no statistically significant difference as compared to the yield of genomic DNA extracted from newly collected swabs (t = 0.59, P > 0.05). In all 65 patients, genomic DNA isolated from either buccal swabs or blood samples showed exactly the same results regarding the genotypes of CFH, LOC387715, and HTRA1 Polymorphisms.
  
  
  CONCLUSIONS
  Buccal swab is a simple, noninvasive, and reliable source for obtaining genomic DNA. Swabs stored for 12 months at -20°C provide similar amount of genomic DNA as the freshly collected swabs.
authors.affiliation: Capital Medical University, Beijing, China.
authors.forename: Yu-le
authors.initials: YL
authors.lastname: Xu
authors.forename: Hai-ying
authors.initials: HY
authors.lastname: Zhou
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.forename: Ning-pu
authors.initials: NP
authors.lastname: Liu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004247:DNA / Q000032:analysis / Q000097:blood / Q000235:genetics*; D005240:Feasibility Studies; D005260:Female; D016678:Genome; D005838:Genotype; D006801:Humans; D008268:Macular Degeneration / Q000175:diagnosis* / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009061:Mouth Mucosa / Q000737:chemistry*; D013048:Specimen Handling / Q000379:methods*
chemical_list: D004247:DNA