Phenotypic non-penetrance in granular corneal dystrophy type II.
OBJECTIVE
To report a possible case of phenotypic non-penetrance in granular corneal dystrophy type II (GCD-II).


METHODS
DNA analysis was performed on 11 patients with white granular corneal opacities and 50 normal controls after informed consent was obtained. The TGFBI gene was analyzed by sequencing DNA from epidermal keratinocytes obtained using adhesive tape.


RESULTS
The heterozygous R124H mutation of TGFBI gene was found in all 11 patients. Although 49 normal controls had no mutation in the TGFBI gene, one normal control, a 26-year-old man, had the heterozygous R124H mutation of TGFBI gene. His 55-year-old father had the same mutation, but no corneal opacities.


CONCLUSIONS
As not all mutations are expressed in the phenotype, GCD-II gene mutation may have non-penetrance. This report documents a possible case of phenotypic non-penetrance in GCD-II.
Kim
Jung-Wan
JW
Department of Ophthalmology, Korea University College of Medicine, Seoul, Republic of Korea.
Kim
Hyo-Myung
HM
Song
Jong-Suk
JS
D000328:Adult; D001120:Arginine; D001483:Base Sequence; D003317:Corneal Dystrophies, Hereditary / Q000145:classification / Q000235:genetics* / Q000473:pathology; D003318:Corneal Opacity / Q000209:etiology / Q000235:genetics; D004817:Epidermis / Q000378:metabolism / Q000473:pathology; D016326:Extracellular Matrix Proteins / Q000235:genetics; D006579:Heterozygote; D006639:Histidine; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009154:Mutation; D020125:Mutation, Missense; D019683:Penetrance; D010641:Phenotype; D016212:Transforming Growth Factor beta / Q000235:genetics; D000099222:betaIG-H3 Protein
D001120:Arginine; D016326:Extracellular Matrix Proteins; D006639:Histidine; D016212:Transforming Growth Factor beta; D000099222:betaIG-H3 Protein