Novel Pathogenic Variants in IFT140 and IFT172 Genes in Three Patients with Similar Retinal Dystrophy Phenotypes.

Introduction: The intraflagellar transport (IFT) complex plays a key role in protein transport and turnover within photoreceptors. IFT140 and IFT172 gene mutations have been associated with skeletal ciliopathies that occur concurrently with retinal dystrophy. These mutations have also been associated with non-syndromic retinal dystrophies. This phenotypic heterogeneity can make diagnosis challenging. Here, we report novel variants in IFT140 and IFT172 genes in 3 patients with similar retinal dystrophy phenotypes.

Case presentations: Two siblings (a 51-year-old male and 46-year-old male) who presented with a similar retinal dystrophy, skeletal abnormalities, and kidney disease were found to have the same novel variant in the IFT140 gene, along with another, previously reported variant. An unrelated individual with a similar retinal phenotype was found to have a novel variant in the IFT172 gene, although this was noted as a variant of uncertain significance. The patients underwent testing with the Blueprint Genetics (Blueprint Genetics Oy, Keilaranta 16 A-B, 02150 Espoo, Finland) "My Retina Tracker Program Panel Plus" panel.

Conclusion: Novel variants in the IFT140 and IFT172 genes encoding the IFT complex may contribute to similar retinal dystrophy phenotypes, as noted in our case series.