PURPOSE: Molecular genetic diagnostics for retinoblastoma are prerequisite for accurate risk prediction and effective management. Developing a retinoblastoma diagnostic model to establish a flow for laboratory tests is thus a necessity for tertiary ophthalmic institutions. An efficient diagnostic model could reduce the overall health care costs, redirect the resources to the high risk group and also avoid unnecessary worry for families. To the best of our knowledge there has hitherto been no comprehensive diagnostic model for retinoblastoma implemented in any institution in India. METHODS AND DISCUSSION: The diagnostic model demonstrates the logical and practical flow of various genetics tests like karyotyping, loss of heterozygosity analysis, molecular deletion, linkage analysis (familial cases), mutation screening of -CGA exons first and then non-CGA exons, methylation screening of RB1 and essential promoter regions screening in a laboratory. CONCLUSIONS: The diagnostic model proposed offers acomprehensive methodology to identify the causative two-hits for retinoblastomas that could be used while genetic counseling families. This model is applicable in tertiary hospitals in India and neighboring countries, which have the highest incidence of retinoblastoma and fertility rates in the world. We suggest that this diagnostic model could also be applied with modification for other cancers.
PURPOSE: Molecular genetic diagnostics for retinoblastoma are prerequisite for accurate risk prediction and effective management. Developing a retinoblastoma diagnostic model to establish a flow for laboratory tests is thus a necessity for tertiary ophthalmic institutions. An efficient diagnostic model could reduce the overall health care costs, redirect the resources to the high risk group and also avoid unnecessary worry for families. To the best of our knowledge there has hitherto been no comprehensive diagnostic model for retinoblastoma implemented in any institution in India. METHODS AND DISCUSSION: The diagnostic model demonstrates the logical and practical flow of various genetics tests like karyotyping, loss of heterozygosity analysis, molecular deletion, linkage analysis (familial cases), mutation screening of -CGA exons first and then non-CGA exons, methylation screening of RB1 and essential promoter regions screening in a laboratory. CONCLUSIONS: The diagnostic model proposed offers acomprehensive methodology to identify the causative two-hits for retinoblastomas that could be used while genetic counseling families. This model is applicable in tertiary hospitals in India and neighboring countries, which have the highest incidence of retinoblastoma and fertility rates in the world. We suggest that this diagnostic model could also be applied with modification for other cancers.