29. Large deletion of cyp1b1 in a case of primary congenital glaucoma identified with mlpa

Tran Thu Ha, Dao Thi Mai Anh, Nguyen Van Huy, Tran Van Khanh

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Abstract

Primary congenital glaucoma (PCG) is an inherited ocular abnormality that is caused by mutation in CYP1B1 gene. Report of large deletion or gene copy number variants of CYP1B1 in PCG is uncommon. In this case report we describe a rare case of PCG with whole CYP1B1 deletion with implication for changes in detecting mutation of CYP1B1 gene. Clinical, ophthalmological, genetic, and pedigree information of the proband is described and discussed in detail in this case report. The deletion was identified using the Multiplex ligation-dependent probe amplification (MLPA) method. Whole deletion of CYP1B1 was identified using MLPA. Intra ocular pressure (IOP) of the right eye was 38mmHg and that of the left eye was 35mmHg. Corneal diameters of both eyes were 13mm horizontal and 12mm vertical. The patient underwent a total of five operations with the first operation performed when he was 2.5 months old. Further investigation revealed that the patient’s grandfather was exposed to a large quantity of 2,3,7,8-tetrachlorodibenzo-p-dioxin. CYP1B1 deletion albeit rare can cause Primary Congenital Glaucoma with poor prognosis and MLPA should be used to detect large deletion and gene copy number variation when sequencing method fails to detect mutations.

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References

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