Research Article - Asian Journal of Biomedical and Pharmaceutical Sciences (2016) Volume 6, Issue 59

A G to C mutation in the CRYGD gamma crystallin gene associated autosomal dominant congenital cataract in Calabar

Introduction: Congenital cataract is particularly important as it is the leading cause of blindness and severe visual impairment in children in Africa, accounting for at least 35% of blindness and severe visual impairment. This study seeks to identify mutations in the gamma crystallin gene that are associated with congenital cataract in some children attending the Eye Clinic in Calabar. Methods: Children (11) with congenital cataract attending the University of Calabar teaching Hospital (UCTH) Pediatric Ophthalmology and Strabismus Unit, Department of Opthalmology. 11 unrelated and unmatched controls that had no history of cataract were recruited into the study. 2-3 ml of blood was collected from each child, DNA was extracted from the blood, and PCR amplifications were carried out. About 25 μl of the PCR amplicon was used for sequencing. Multiple sequence alignment and pairwise comparison of the crystallin gene was carried out in the Mega 7 software. Results: The PCR amplication revealed a 742 bp amplicon which was sent for sequencing. In silico analysis revealed a substitution of guanine by cytosine at position 248 (g.248 G>C) that resulted in an amino acid substitution of arginine by proline at position 83 (p.R83P) in 7 (63.63%) out of the 11 patients. This substitution was absent in 4 patients (36.4%) and in the control subjects. Conclusion: This study identified a G>C substitution at position 248 in the crystallin gene in 7 out of 11 congenital patients and this forms a baseline research for further molecular studies among cataract patients in Calabar.

Author(s): Mary E Kooffreh, Roseline Duke, Anthony Umoyen

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