First Turkish case with UNC80 deficiency

Objectives The UNC80 gene encodes important proteins in the structure of a trimeric channel protein permeable to Na,K+ and Ca+2(NALCN),which are also found in neurons.UNC80 gene mutation,a phenotype of NALCN mutation,is characterized by infantile hypotonia,psychomotor developmental delay and characteristic facial appearance. Methods A 6-year-old 9-month-old male patient presented with hypotonia at the age of one year.His prenatal,perinatal and postnatal history were unremarkable.He was able to sitting at 10 months,walking at 16 months and but still not to start speaking.In addition to dysmorphic findings such as frontal bossing and bullous nasal structure,there was significant axial hypotonia and failure to thrive.Laboratory examinations revealed high transaminase values and normal metabolic examinations.Brain MRI and spectroscopy and also liver biopsy,lysosomal enzyme scanning were normal.No mutations were found in NPC1, NPC2 and Gaucher gene analysis. A homozygous c.840C>G p.(Ile280Met) mutation was detected in the UNC80 gene in the whole exome analysis of the patient whose karyotype and microarray analysis were normal. Results UNC80 mutations are characterized by hypotonia,developmental delay,intellectual disability,intrauterine growth retardation,failure to thrive with characteristic facial features.Speech and walking delay,seizures,growth problems,severe constipation,and feeding difficulties that require gastric tube insertion at an early age can be seen,and also Joint deformities,repetitive movements,and nystagmus may accompany.Unlike the cases in the literature,this case had an unexplained elevation of transaminases. Conclusion To our knowledge,this case is the first Turkish patient with UNC80 deficiency syndrome.In addition,elevated transaminase levels in a patient with UNC80 deficiency syndrome are reported for the first time and expand the clinical spectrum of the syndrome.