Abstract
Purpose :
Inherited retinal degenerations (IRDs) consist of a number of severe retinal degenerative diseases with great genetic and clinical heterogeneity. These diseases, caused by degradation of rod and cone photoreceptor cells, lead to a progressive loss of vision. Genetic diagnosis is becoming much feasible with the development of next-generation sequencing (NGS) technique. Here we present our experience for patients with or without family history.
Methods :
The reported cases were recruited in the TIP (Taiwan Inherited retinal diseases Project) program. The blood sample was collected and the genomic DNA was sequenced by panel-based next-generation sequencing (NGS) with 215 genes associated with inherited retinal degenerations. NGS data were processed and pathogenicity of retained variants was predicted by algorithm analysis such as SIFT, PolyPhen-2, and database such as GnomAD. The criteria of classifying pathogenic variants were based on the ACMG standard and guideline.
Results :
In our first 60 probands recruited in TIP program, 37 (62%) of them could recall positive family histories while 23 (38%) of them denied any family history of IRDs. Among them, 20 of the 37 probands (54%) with a positive family history got a genetic diagnosis with our panel-based NGS test. On the other hand, 11 of the 23 probands (48%) with a negative family history also got a genetic diagnosis with our panel-based NGS test. The total diagnostic rate of these patients was 52%, comparable with the data reported in other developed countries.
Conclusions :
Here we report our experiences in genetic diagnosis using panel-based NGS for inherited retinal degenerations (IRDs) in east Asia and the comparison of diagnostic rate between patients with or without family histories. In our current experience, the diagnostic power is similar for both groups. These findings confirm the value of NGS technique for IRDs and might be useful for genetic consultation and even selecting candidates for gene therapy in the near future.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.