在两名患有胶滴状角膜营养不良的中国兄弟中鉴定出一种新的TACSTD2突变。

PURPOSE

To identify the molecular defect causing gelatinous drop-like corneal dystrophy (GDLD) in two Chinese brothers and report the morphological evaluation of GDLD by laser scanning confocal microscopy and Fourier-domain optical coherence tomography (OCT).

METHODS

Genetic analysis included polymerase chain reaction (PCR) amplification and direct nucleotide sequencing of the coding region of the tumor-associated calcium signal transducer 2 gene (TACSTD2) in DNA from the two brothers and their relatives. Laser scanning confocal microscopy and Fourier-domain OCT were performed on the left cornea of the younger brother.

RESULTS

We report a novel in-frame mutation of TACSTD2, c.526_576del 51, in the two brothers with GDLD. The identified molecular defect cosegregated with the disease and was not found in 50 unaffected individuals. The morphological evaluation on GDLD highlighted pathological observations at the level of epithelium and anterior stroma. The epithelial cells of GDLD cornea were irregular in shape and often elongated. Large accumulations of brightly reflective amyloid material was noted within or beneath the epithelium and within the anterior stroma.

CONCLUSIONS

The newly identified mutation expands the spectrum of mutations in TACSTD2 that may cause pathological corneal amyloidosis. Observations by in vivo confocal microscopy and Fourier-domain OCT were consistent with the histopathologic descriptions of GDLD.

目的

确定导致两名中国兄弟患胶冻样滴状角膜营养不良（GDLD）的分子缺陷，并报告通过激光扫描共聚焦显微镜和傅里叶域光学相干断层扫描（OCT）对GDLD进行的形态学评估。

方法

基因分析包括对两兄弟及其亲属的DNA中肿瘤相关钙信号转导蛋白2基因（TACSTD2）编码区进行聚合酶链反应（PCR）扩增和直接核苷酸测序。对弟弟的左眼进行激光扫描共聚焦显微镜和傅里叶域OCT检查。

结果

我们报告了两名患有GDLD的兄弟中TACSTD2基因的一种新的框内突变，即c.526_576del 51。所鉴定的分子缺陷与疾病共分离，在50名未受影响的个体中未发现。对GDLD的形态学评估突出了上皮和前基质水平的病理观察结果。GDLD角膜的上皮细胞形状不规则，常呈拉长状。在上皮内或上皮下以及前基质内可见大量明亮反射性淀粉样物质堆积。