A clinical and molecular genetic study of Egyptian and Saudi Arabian patients with primary congenital glaucoma (PCG).
OBJECTIVE
To undertake mutation screening of cytochrome P4501B1 (CYP1B1, OMIM 601771) and myocilin (MYOC, OMIM 601652) genes in Egyptian and Saudi Arabian patients with primary congenital glaucoma (PCG).


METHODS
A clinical and molecular genetic study was performed on 11 Egyptian and Saudi Arabian patients with PCG. Clinical diagnosis was confirmed by slit lamp biomicroscopy, gonioscopy, measurement of intraocular pressure, and corneal diameter. The coding regions of CYP1B1 and MYOC genes were amplified by polymerase chain reaction for all affected subjects. Direct sequence analysis was performed to search for sequence alterations. Haplotype analysis and genotype/phenotype correlation were carried out.


RESULTS
Three CYP1B1 mutations were identified in 5 PCG patients (45.4%) of which 2 were novel (homozygous E173K and heterozygous N498D) and the third (G61E) had previously been reported. In addition 10 single nucleotide polymorphisms were identified in CYP1B1 and MYOC genes of which 2 were novel. However, no pathologic changes in either of the genes were detected in the remaining 6 patients.


CONCLUSIONS
This is the first report of molecular genetic analysis of PCG in the Egyptian population in which 2 novel mutations have been identified. It is possible that these mutations are specific to this population and may lead to alterations in the protein structure encoded by the gene. Patients with no mutations in the screened genes may have mutations in genes yet to be identified.
El-Ashry
Mohamed F
MF
Department of Molecular Genetics, Institute of Ophthalmology, London EC1V 9EL, UK. elashrymohamed@yahoo.co.uk
Abd El-Aziz
Mai M
MM
Bhattacharya
Shomi S
SS
D017668:Age of Onset; D000595:Amino Acid Sequence; D001189:Aryl Hydrocarbon Hydroxylases; D002648:Child; D002675:Child, Preschool; D003241:Consanguinity; D065633:Cytochrome P-450 CYP1B1; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics*; D003598:Cytoskeletal Proteins / Q000235:genetics*; D004252:DNA Mutational Analysis; D004534:Egypt / Q000453:epidemiology; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D005901:Glaucoma / Q000151:congenital / Q000208:ethnology / Q000235:genetics*; D006023:Glycoproteins / Q000235:genetics*; D006068:Gonioscopy; D006239:Haplotypes; D006801:Humans; D007223:Infant; D007429:Intraocular Pressure; D008297:Male; D008967:Molecular Biology; D008969:Molecular Sequence Data; D009154:Mutation; D010375:Pedigree; D016133:Polymerase Chain Reaction; D012529:Saudi Arabia / Q000453:epidemiology; D000099179:Myocilin
D001189:Aryl Hydrocarbon Hydroxylases; D065633:Cytochrome P-450 CYP1B1; D003577:Cytochrome P-450 Enzyme System; D003598:Cytoskeletal Proteins; D005136:Eye Proteins; D006023:Glycoproteins; D000099179:Myocilin; C585496:CYP1B1 protein, human