%0 Case Reports
%T Retrocollis as the cardinal feature in a de novo ITRP1 variant.
%A Zachou A
%A Palaiologou D
%A Kanavakis E
%A Anagnostou E
%A Zachou A
%A Palaiologou D
%A Kanavakis E
%A Anagnostou E
%J Brain Dev
%V 44
%N 5
%D May 2022
%M 35148930
%F 2.272
%R 10.1016/j.braindev.2022.01.005
%X <B>BACKGROUND: </B>ITPR1 gene encodes inositol 1,4,5-trisphosphate-receptor-type 1, a Ca2+ channel highly expressed in cerebellar Purkinje cells. ITPR1 gene variants, through a loss-of-function mechanism, have been found to be related with the manifestation of spinocerebellar ataxia (SCA) 15, an adult-onset slow progressive cerebellar ataxia, SCA 29, a rare non-progressive congenital cerebellar ataxia and Gillepsie syndrome (SCA 29 phenotype plus aniridia). They share an heterogeneity of additional phenotypic features while no genotype-phenotype correlation has ever been found.<BR><B>METHODS: </B>Here we report the case of a boy with cerebellar ataxia who came to our clinic due to his cervical dystonia in the form of retrocollis. He presented an early-onset, non-progressive cerebellar ataxia, with cognitive impairment and delayed motor milestones. Whole exome sequencing (WES) revealed an heterozygous nucleotide variation, c.829A > C (p.Ser277Arg) in ITPR1 gene (NM_001168272.1), a de novo ITPR1 variant, as his parents came up with negative genetic testing. Due to his clinical presentation and genetic result, we came up with the diagnosis of SCA 29.<BR><B>CONCLUSIONS: </B>We described cervical dystonia as a phenotypic feature of ITPR1 related SCA 29, found in a new de novo ITPR1-variant.