Mutation Analysis of the TGFBI Gene in Consecutive Korean Patients With Corneal Dystrophies.
BACKGROUND
Mutations in the transforming growth factor β-induced gene (TGFBI) are major causes of genetic corneal dystrophies (CDs), which can be grouped into TGFBI CDs. Although a few studies have reported the clinical and genetic features of Korean patients with TGFBI CD, no data are available regarding the frequency and spectrum of TGFBI mutations in a consecutive series of Korean patients with clinically diagnosed CDs.


METHODS
Patients with any type of CD, who underwent both ophthalmologic examination and TGFBI gene analysis by Sanger sequencing at a tertiary care hospital in Seoul, Korea from 2006 to 2013, were enrolled in this study.


RESULTS
Among a total of 89 patients, 77 (86.5%) were diagnosed as having clinical TGFBI CD. Seventy-three out of 74 patients (98.6%) with granular CD type 2 (GCD2), had the p.R124H mutation. Of particular note, one patient with rapidly progressive CD had the p.R124H mutation as well as a novel nonsense variant with unknown clinical significance (p.A179*). In three patients with lattice CD type 1 (LCD1), one known mutation (p.R124C) and two novel variants (p.L569Q and p.T621P) in the TGFBI gene were identified.


CONCLUSIONS
This study provides epidemiological insight into CDs in a Korean population and reaffirms that GCD2 is the most common TGFBI CD phenotype and that p.R124H is the only mutation identified in patients with GCD2. In addition, we broaden the spectrum of TGFBI mutations by identifying two novel missense variants in patients with LCD1.
Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Ju Sun
JS
Song
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea. ; Department of Preventive Medicine, Catholic University School of Medicine, Seoul, Korea.
Dong Hui
DH
Lim
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Eui-Sang
ES
Chung
Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Tae-Young
TY
Chung
Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Chang-Seok
CS
Ki
D000293:Adolescent; D000328:Adult; D000368:Aged; D044466:Asian People / Q000235:genetics*; D003317:Corneal Dystrophies, Hereditary / Q000175:diagnosis / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D056910:Republic of Korea; D012189:Retrospective Studies; D053773:Transforming Growth Factor beta1 / Q000235:genetics*; D055815:Young Adult
C508960:TGFB1 protein, human; D053773:Transforming Growth Factor beta1
Granular corneal dystrophy type 2; Korean; Lattice corneal dystrophy type 1; Mutation; TGFBI