上皮基底膜角膜营养不良家系的TGFBI基因突变1例研究

Stufy on the TGFBI gene in a Chinese family with epithelial basement membrane dystrophy

目的:检测1例中国上皮基底膜角膜营养不良家系TGFBI基因突变类型。方法:经过详细的病史采集及临床检查后,提取先证者及其家系内其他2例患者和4例有血缘关系的正常家系成员的静脉血白细胞DNA,应用PCR直接测序法对TGFBI的17个外显子进行候选基因的突变检测。结果:在该家系患者的TGFBI基因4号外显子发现了c.417C>T,导致了杂合突变R124C。家系中正常成员及对照组均未检测到该突变。结论:本研究首次报道了TGFBI基因的R124C杂合突变导致了上皮基底膜角膜营养不良,拓宽了角膜营养不良的基因型与表现型关系,为进一步的分子遗传学研究奠定了基础。

AIM： To identify the mutation within the TGFBI gene in a Chinese family with epithelial basement membrane dystrophy（EBMD）.METHODS： A detailed family history was collected and after full clinical examination, genomic DNA of three affected and four unaffected family members was extracted from peripheral leukocytes. All exons of TGFBI gene were amplified by PCR methods and direct sequencing was carried out for mutation analysis.RESULTS： A missense mutation c.417C〉T in exon 4 of TGFBI led to an amino acid substitution R124C which was responsible for the familial disorder. This change co-segregated with all affected members of the family, but was not detected either in the non-carrier relative or control individuals.CONCLUSION： This is the first report of the R124C mutation within the TGFBI gene in EBMD. The results broaden the relationship between genotype and phenotype of corneal dystrophy, and establish the foundation for the further molecular genetics studies.