Childhood-onset primary open angle glaucoma in a Canadian kindred: clinical and molecular genetic features.

OBJECTIVE

To describe the clinical features and identify the molecular etiology of childhood-onset primary open angle glaucoma (POAG) in a Canadian kindred.

METHODS

Members of a Canadian Caucasian family with POAG were examined and DNA obtained. Single-strand conformation polymorphism analysis was performed using reported primers from exon 3 of the myocilin gene. A single-stranded conformation polymorphism was characterized by polymerase chain reaction-based sequencing.

RESULTS

Two affected half-sibs had onset of severe glaucoma at age 3 and 9. Their mother had lost vision in one eye from glaucoma by age 17. All three affected subjects had undergone bilateral glaucoma filtering surgery. Both fathers were unaffected. A single-stranded conformation polymorphism was identified in the mother and the two affected daughters and was absent in one father. A single base change from C-->T at nucleotide position 1109 was identified in the affected members of the family by direct sequencing. This mutation, which causes a nonconservative amino acid change (Pro370Leu), was not found on 192 normal chromosomes from Caucasian individuals.

CONCLUSION

We report a Canadian family with childhood-onset, severe POAG due to a mutation in the myocilin gene.