Familial Mediterranean fever gene variations could trigger -associated early-onset dystonia and diabetes mellitus: clinical identification of a family with and genetic variation association.

Objectives: We describe the clinical pictures of an index case with dystonia and his family resulting from and genetic variations based on previously published data and discuss the mechanisms that may have brought out the clinical findings.

Methods: A 17-year-old male had generalized dystonia that started at age 6 years, non-febrile abdominal pain attacks and was diagnosed with type 1 diabetes at age 14 years. Meanwhile, his 13-year-old sister had the same clinical presentation. His father was diabetic and his mother was asymptomatic. There was no consanguinity between the parents. Genetic variations were detected with whole exome sequencing.

Results: c.1513C>T/p.Arg505* (likely pathogenic), c.2080A>G p.Met694val (pathogenic) and c.1772T>C p.Ile591Thr (unknown significance) heterozygous variants were detected in his siblings. The father had c.1513C>T/p.Arg505* and c.2080A>G p Met694val variations and the mother had c.1772T>C p.Ile591Thr variations.

Conclusions: The occurrence of these diseases in siblings but their absence in the parents suggests the idea that the coexistence of two separate variations in the and genes determines the phenotype. In addition, the increase in variation load in this family and the fact that DM occurs at an earlier age suggest that inflammation may cause an early diabetic clinical presentation.