Glaucoma, congenital

CYP1B1 (chromosome 5) has been linked to primary congenital glaucoma. CYP1B1 is not regularly expressed in liver but is often found in various kinds of tumours. It metabolizes retinoids and many aromatic amines and PAHs to potentially carcinogenic products. 

Monnet et al. (M12) report that among 15 children below one year of age, suffering from congenital glaucoma, one developed a typical Lowe syndrome and four others presented hyperamino aciduria as the only extra pathological feature. In three other cases of this disease (two brothers and one third cousin), one of which reached adult age, there was a definite hyperamino aciduria, namely, a large excretion of glutamic acid by the two brothers (G4). 

CYP1B1 Amino acid Frameshifts Loss of function Unknown Mutations occur in primary congenital glaucoma... 

CYP1B1 is also expressed in the fetus in multiple tissues, particularly in thymus, spleen, kidney, and adrenal. A null CYP1B1 phenotype in humans has been associated with appearance of primary congenital glaucoma. Consistent with an important endogenous role for this enzyme in development of the eye, CYP1B1—which, in addition to biotransformation of xenobiotics, is also capable of metabolizing retinoid and sex steroids—is expressed in embryonic ocular tissues. 

In congenital glaucoma the trabecular network is attached to the iris. Blindness occurs if surgery is not performed to correct this problem. 

Apraclonidine 0.5% can be used for short-term therapy of patients on maximally tolerated medical therapy who require additional reductions in lOP Patients with primary or secondary glaucoma do not appear to differ in either the magnitude or duration of ocular hypotensive response, but patients with developmental or congenital glaucomas tend to respond less satisfectorily. 

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