Compound heterozygous mutations in the LTBP2 gene associated with microspherophakia in a Chinese patient: a case report and literature review

BACKGROUND

Microspherophakia (MSP, OMIM 251,750) is a rare inherited autosomal recessive eye disorder characterized by small spherically shaped lens. Several studies have indicated that the transforming growth factor-beta (TGF-beta) binding proteins(LTBP2) gene mutation is the predominant cause of MSP. In our study, novel compound heterozygous mutations in the LTBP2 gene associated with MSP were reported, which was different from previous reported homozygous mutations.

CASE PRESENTATION

The proband was an 18-year-old male in Western China with bilateral MSP, accompanied by ectopia lentis, secondary glaucoma and blindness in both eyes. In our hospital, he received bilateral lens resection and trabeculectomy combined with peripheral iridotomy. Using next-generation sequencing (NGS)-based gene panel tests, we identified pathogenic mutations in the peripheral blood DNA sample from the proband: c.3614_3618dupCTGGC (exon24, NM_000428) and c.2819G > A (exon18, NM_000428). The presence of the novel compound heterozygous mutations in the LTBP2 gene was linked with the development of MSP. Sanger sequencing confirmed the existence of one of the two variants in each parent respectively.

CONCLUSION

Our results demonstrated a rare case of MSP phenotype associated with novel compound heterozygous mutations in the LTBP2 gene using NGS technology.

Neonatal Marfan syndrome caused by an exon 25 mutation of the fibrillin-1 gene

Neonatal Marfan syndrome caused by an exon 25 mutation of the Fibrillin-1 gene: We describe a male infant with severe arachnodactyly, hypermobility of the fingers, flexion contractures of elbows, wrists, hips, and knees, microretrognathia, crumpled ears, rockerbottom feet, loose redundant skin, and lens dislocations. Cardiac valve insufficiency and aortic dilatation resulted in cardiac failure, decompensated with digitalisation and death occurred at the age of 4 months. This case represents the severe end of the clinical spectrum of Marfan syndrome, namely neonatal Marfan syndrome. Molecular diagnostic analyses confirmed a de novo exon 25 mutation in the FBN1 gene.

Bilateral ectopia lentis in Marfan's syndrome: review of features with report of two cases

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Primordial dwarfism and ectopia lentis

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