Two mutations in the transforming growth factor beta-induced gene associated with familial Lattice corneal dystrophy

AIM：To report a phenotypic variant pedigree of lattice corneal dystrophy（LCD）associated with two mutations,R124C and A546 D,in the transforming growth factor betainduced gene（TGFBI）.METHODS：A detailed ocular examination was taken for all participants of a LCD family. Peripheral blood leukocytes from each participant were extracted to obtain the DNA. Polymerase chain reaction（PCR）of all seventeen exons of TGFBI gene was performed. The products were sequenced and analyzed. Histological examination was carried out after a penetrating keratoplasty from the right eye of proband. RESULTS：Genetic analysis showed that the proband and all 6 affected individuals harbored both a heterozygous CGC to TGC mutation at codon 124 and a heterozygous GCC to GAC mutation at codon 546 of TGFBI. None of the 100 control subjects and unaffected family members was positive for these two mutations. Ocular examination displayed multiple refractile lattice-like opacities in anterior stroma of the central cornea and small granular deposits in the peripheral cornea. The deposits were stained positively with Congo red indicating be amyloid in nature and situated mainly in the anterior and middle stroma. CONCLUSION：We observed a novel LCD family which carried two pathogenic mutations（R124C and A546D）in the TGFBI gene. The phenotypic features were apparently different from those associated with corresponding single mutations. The result reveals that although the definite mutation is the most important genetic cause of the disease,some different modifier alleles may influence the phenotype.

Chinese medicine monomer intervention reduces amyloid beta-induced nerve cell injury

Totally three articles focusing on the protective effects of Schisandrin B, berberine and curcumin against amyloid beta-induced neuronal toxicity were published in three issues. We hope that our readers find these papers useful to their research.

Uncovering the profile of mutations of transforming growth factor beta-induced gene in Chinese corneal dystrophy patients

AIM： To uncover the mutations profile of transforming growth factor beta-induced （TGFBI） gene in Chinese corneal dystrophy patients and further investigate the characteristics of genotype-phenotype correlations. METHODS： Forty-two subjects （6 unrelated families including 15 patients and 8 unaffected members, and 19 sporadic patients） of Chinese origin were subjected to phenotypic and genotypic characterization. The corneal phenotypes of patients were documented by slit lamp photography. Mutation screening of the coding regions of TGFBI was performed by direct sequencing. RESULTS： We detected four corneal dystrophy types. The most frequent phenotypes were granular corneal dystrophy （GCD） （including 3 families and 8 sporadic patients） and lattice corneal dystrophy （LCD） （including 2 families and 9 sporadic patients）. The next phenotypes were corneal dystrophy of Bowman layer （CDB） （1 family and 1 sporadic patient） and epithelial basement membrane dystrophy （EBMD） （1 sporadic patient）. Six distinct mutations responsible for TGFBI corneal dystrophies were identified in 30 individuals with corneal dystrophies. Those were, p.R124H mutation in 1 family and 2 sporadic patients with GCD, p.R555W mutation in 2 families and 3 sporadic patients with GCD, p.R124C mutation in 2 families and 7 sporadic patients with LCD, p.A620D mutation in 1 sporadic patient with LCD, p.H626R mutation in 1 sporadic patient with LCD, and p.R555Q in 1 family and 1 sporadic patient with CDB. No mutation was detected in the remaining 3 atypical GCD patients and 1 EBMD patient, CONCLUSION： GCD and LCD are the most frequent phenotypes in Chinese population. R555W was the most common mutation for GCD; R124C was the most common mutation for LCD, Our findings extend the mutational spectrum of TFGBI , and this is the extensively delineated TGFBI mutation profile associated with the various corneal dystrophies in the Chinese population.