Next Generation Sequencing Based Multiplex Long-Range PCR for Routine Genotyping of Autoinflammatory Disorders

Screening of OTULIN gene mutation with targeted next generation sequencing in Turkish populations and in silico analysis of these mutations

BACKGROUND

OTULIN-related autoinflammatory syndrome (ORAS) is an autosomal recessive disease characterized by systemic inflammation, recurrent fever. Due to limited knowledge about the OTULIN DNA variants that cause ORAS, the diagnosis and treatment of this disease is difficult. In this study, we aim to identify OTULIN DNA variants responsible for the genetic pathology of ORAS and observe the effects of these variants on the OTULIN protein structure and the function with different bioinformatics approaches.

METHODS

The present study included 3230 individuals with the suspicion of an autoinflammatory disease who were referred to Ege University Children's Hospital Molecular Medicine Laboratory. OTULIN variants were detected using a panel consisting of 37 different autoinflammatory diseases (AID) genes via targeted Next-Generation Sequencing.

RESULTS

As a result of the study, DNA variants associated with various AID were detected in 65% of the individuals to whom the panel was applied. Among these variants, only three different OTULIN variants (p.Val82Ile, p.Gln115His and p.Leu131_Arg132insLeuCysThrGlu) were detected. The pathogenic effects of the variants detected in the OTULIN gene were determined by using Polyphen2 as "Probably Pathogenic" for the p.Val82Ile and "benign" for the p.Gln115His. At the same time, the effects of these variants on the structure and function of the OTULIN protein were investigated by in silico approaches. Both variants reduce protein stability and binding affinity.

CONCLUSION

The results of the current study suggest that the evaluation of OTULIN variants with in silico approaches will contribute to the development of personalized treatments by diagnosing the disease specific to the variant.

Conventional and novel therapeutic options in children with familial Mediterranean fever: A rare autoinflammatory disease

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease and is usually diagnosed in childhood, especially in the first decade of life. Paediatric FMF is characterized by a protean clinical expression and a variable therapeutic response, which can make its medical management very challenging. However, even if long-term complications of untreated FMF (e.g. amyloidosis and related organ damage) are less frequent in children compared to adults, they are not uncommon. Colchicine is the mainstay of the therapy in paediatric FMF; however, if children develop colchicine intolerance and/or resistance, biologics, particularly interleukin-1 antagonists, must be considered. Other conventional or biological therapeutic options do not currently have appropriate evidence-based support, except for some specific clinical presentations (e.g., arthritis). In this review, we discuss the biological basis and the clinical evidence for the current pharmacological treatment options available for paediatric FMF.