Molecular analysis of CYP1B1 in Omani patients with primary congenital glaucoma: a pilot study.
OBJECTIVE
To screen cytochrome P4501B1 (CYP1B1) for causative mutations in Omani patients with a clinical diagnosis of primary congenital glaucoma (PCG) METHODS: Nine PCG families were recruited for the study. All patients underwent detailed clinical examinations to confirm the diagnosis of PCG. The families of index patients were also examined. Genealogical information was obtained by pedigree analysis. The primary candidate gene, CYP1B1, was amplified from genomic DNA, sequenced, and analyzed in patients to identify the disease-causing mutations.


RESULTS
Eight of the nine PCG families were consanguineous (89%). Molecular analysis of CYP1B1 showed three distinct mutations, p.G61E, p.D374N, and p.R368H, in seven of nine unrelated PCG index patients (78%). Six patients had homozygous mutations and one had a compound heterozygous mutation. Causative mutations were not identified in two families. In family 4, the index patient was found to be heterozygous for the p.E229K variant. In family 6, although affected individuals were found to be homozygous in the CYP1B1 region, no mutation could be identified.


CONCLUSIONS
This study indicates that CYP1B1 could be the predominant cause of PCG in the Omani population (78%). Omani PCG patients show allelic heterogeneity. Further studies are needed to delineate the spectrum of CYP1B1mutations in Omani PCG families and to identify new or modifier genes contributing to the manifestations of PCG in this region.
El-Gayar
Stefan
S
Department of Ophthalmology, Sultan Qaboos University Hospital, Muscat, Oman.
Ganesh
Anuradha
A
Chavarria-Soley
Gabriela
G
Al-Zuhaibi
Sana
S
Al-Mjeni
Rayhanah
R
Raeburn
Sandy
S
Bialasiewicz
Alexander A
AA
D000293:Adolescent; D000328:Adult; D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics*; D044466:Asian People / Q000235:genetics*; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D065633:Cytochrome P-450 CYP1B1; D005260:Female; D005901:Glaucoma / Q000151:congenital* / Q000201:enzymology* / Q000235:genetics; D006239:Haplotypes; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D009850:Oman; D010375:Pedigree; D010865:Pilot Projects
D001189:Aryl Hydrocarbon Hydroxylases; C585496:CYP1B1 protein, human; D065633:Cytochrome P-450 CYP1B1