Ectopia lentis associated with primary congenital glaucoma

Next-generation sequencing panel analysis in 24 Chinese patients with congenital ectopia lentis

BACKGROUND

Congenital ectopia lentis (CEL) is a rare but serious disease. We use next-generation sequencing to detect genes associated with lens abnormalities in 24 patients with bilateral CEL and search for pathogenic genes and mutation sites.

MATERIALS AND METHODS

A total of 24 patients diagnosed with CEL from January 2019 to November 2019 were enrolled in this study, and their clinical data were collected and genome-wide deoxyribonucleic acid was extracted from peripheral venous blood. Targeted gene capture technology was used to obtain 188 exons of lens abnormality-related genes, which were sequenced using a high-throughput method. The mutation sites were determined through data analysis and verified by the Sanger method. According to the data from previous studies, the association between the genotype and clinical phenotype was analysed.

RESULT

Of the 24 patients, 23 had mutations in the fibrillin-1 (FBN1) gene, and 20 were diagnosed with Marfan syndrome. The 23 cases of FBN1 mutations were all heterozygous mutations, including 17 missense mutations, 3 splicing variants, 2 exon deletion mutations, 1 codon mutation, and 9 new mutations. A total of 17 mutations were located in the calcium-binding epidermal growth factor domain, including 16 mutations that contained missense mutations of cysteine. In addition, a heterozygous mutation of the gap junction protein alpha 8 (GJA8) gene was detected in one patient.

CONCLUSION

In this study, we identified 23 FBN1 gene mutations and 1 GJA8 gene mutation in 24 patients with CEL. Of these, 9 new FBN1 mutations and 14 known mutations were found. The results expanded the mutation spectrum of the FBN1 gene, suggesting that FBN1 mutation may be the main cause of CEL in Chinese patients.

Characteristics and Risk Factors for Pupillary Capture of Intraocular Lens in Congenital Ectopia Lentis

Importance: To analyze the characteristics and risk factors for pupillary capture (PC) of the intraocular lens (IOL) in congenital ectopia lentis (CEL) patients.Methods: Data of CEL patients who underwent lens extraction and intraocular implantation from 2013 to 2016 at Zhongshan Ophthalmic Center in China were collected. Best-corrected visual acuity (BCVA), axial length (AL), refractive status, corneal curvature, intraocular pressure (IOP), degree of lens dislocation, presence of strabismus, and methods of IOL fixation were recorded. Postoperative data were collected from the routine one-month postoperative follow-up. Patients with PC of IOL were characterized and risk factors for PC of IOL were analyzed using age-sex adjusted multiple logistic regression analysis.Results: Of the 89 included CEL subjects, 43.8% (39/89) of them suffered from PC after IOL implantation. There was no statistically significant difference in BCVA, AL, refractive status and IOP between the eyes which developed PC versus those which did not. Age-sex multiple logistic regression analysis shows that PC of IOL was associated with a more severe degree of lens dislocation and eyes with strabismus before surgery.Conclusions: Eyes with strabismus and more severe degrees of lens dislocation before surgery are risk factors for PC of IOL. When treating patients that present these risk factors, preoperative communication, and postoperative follow-up should be strengthened. Considering that PC of IOL has little effect on visual acuity, patients with slight PC of IOL can be exempt from surgical intervention.