The usefulness of buccal swabs for mutation screening in patients with suspected corneal dystrophies.
OBJECTIVE
To make ophthalmologists aware of the usefulness of buccal swabs for the collection of cells from which DNA may be extracted to be used in genetic screening of patients with known or suspected inherited ocular disorders, such as corneal dystrophies.


METHODS
Illustrative interventional case report.


METHODS
Buccal epithelial swabs were collected from a 3-year-old boy with a presumed corneal dystrophy and his unaffected parents. Swabs were mailed to a laboratory where transforming growth factor-beta-induced gene (TGFBI) mutation screening was performed.


METHODS
Results of sequencing TGFBI exons 4 and 12.


RESULTS
Transforming growth factor-beta-induced gene mutation screening in a child with bilateral anterior corneal stromal opacification revealed the following changes in exon 12: 1667T>C (Phe540Phe), 1684C>A (Ala546Asp), and 1699C>A (Pro551Gln). The child's father demonstrated the 1667T>C nucleotide substitution, but neither parent demonstrated the 1684T>C or the 1699C>A changes.


CONCLUSIONS
Buccal swabs provide the ophthalmologist with a simple, inexpensive means of collecting and transporting cells from which DNA may be extracted to be used to either confirm or refute diagnoses solely on the basis of clinical features. In this case, the diagnosis of an atypical variant of lattice corneal dystrophy was made on the basis of the identification of previously reported mutations in TGFBI.
Aldave
Anthony J
AJ
Department of Ophthalmology, The University of California, San Francisco/Francis I. Proctor Foundation, San Francisco, California 90095, USA. aldave@jsei.ucla.edu
Yellore
Vivek S
VS
Self
Cynthia A
CA
Holsclaw
Doug
D
Small
Kent
K
D002675:Child, Preschool; D003317:Corneal Dystrophies, Hereditary / Q000235:genetics*; D004247:DNA / Q000302:isolation & purification; D004252:DNA Mutational Analysis; D005091:Exons / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D005820:Genetic Testing / Q000379:methods*; D006801:Humans; D008297:Male; D009061:Mouth Mucosa / Q000166:cytology*; D009154:Mutation / Q000235:genetics*; D016212:Transforming Growth Factor beta / Q000235:genetics*; D000099222:betaIG-H3 Protein
D004247:DNA; D016326:Extracellular Matrix Proteins; D016212:Transforming Growth Factor beta; D000099222:betaIG-H3 Protein