Whole exome sequencing analysis and prenatal diagnosis for a Chinese pedigree affected with microphthalmia

OBJECTIVE To analyze clinical features and genetic cause for a Chinese pedigree affected with microphthalmia. METHODS The proband and his parents were subjected to whole exome sequencing (WES) to identify potential pathogenic variants. Sanger sequencing was carried out to confirm the result of WES in available members from the pedigree. Prenatal diagnosis was provided to the proband's mother by genetic testing of amnionic DNA. RESULTS A heterozygous nonsense mutation c.289C>T (p.R97*) was identified in the OTX2 gene among three patients from the pedigree by WES. The result was confirmed by Sanger sequencing. The proband's mother has carried the same mutation but did not have microphthalmia. The proband's father, aunt and the mother's fetus did not carry the mutation. CONCLUSION The c.289C>T (p.R97*) mutation probably underlies the microphthalmia in this pedigree. Above result has facilitated genetic counseling and prenatal diagnosis.