Prenatal diagnosis of Sex determining region Y -box transcription factor ۲ anophthalmia syndrome caused by germline mosaicism using next-generation sequencing: A case report

Background: Sex determining region Y box transcription factor ۲ (SOX۲) mutations lead to bilateral anophthalmia with autosomal dominant human inheritance. SOX۲ mutations could result in severe ocular phenotypes usually associated with variable systemic defects. Most patients described with SOX۲ anophthalmia syndrome possessed de novo mutations in this gene. Case Presentation: In this case report, we describe ۲ brothers with mental retardation and bilateral anophthalmia caused due to SOX۲ germline mosaicism in unaffected parents. Next-generation DNA sequencing was carried out to determine the family’s possible cause of genetic mutation. Sanger sequencing was performed on the patients and their parents. Prenatal diagnosis was done in both pregnancies of the older brother’s wife via chorionic villus sampling. A novel heterozygous pathogenic frameshift deletion variant (exon۱:c.۵۸_۸۰del:p.G۲۰fs) was identified in the SOX۲ gene, which was confirmed by Sanger sequencing in both affected brothers and did not exist in healthy parents, indicating germline mosaicism. Conclusion: Most SOX۲ mutations known look to arise de novo in probands and are diagnosed through anophthalmia or microphthalmia. Prenatal diagnosis should be offered to healthy parents with a child with SOX۲ mutation every pregnancy.

کلیدواژه ها:

Anophthalmos ، SOX۲ anophthalmia syndrome ، Mosaicism. ، آنفتالموس ، سندرم آنوفتالمی SOX۲ ، موزاییسم.