Neurol Sci (2013) 34:569-571 DOI 10.1007/s 10072-012-1183-x KIF21A mRNA expression in patients with Down syndrome Michele Salemi • Concetta Barone • Carmelo Romano • Federico Ridolfo • Cataldo Scavuzzo • Rita Anna Cantarella • Maria Grazia Salluzzo • Aldo E. Calogero • Corrado Romano • Paolo Bosco Received: 11 July 2012/Acceptecl: 27 August 2012/Puhlished online: 12 September 2012 © Springer-Verlag 2012 Abstract Down syndrome (DS) is a chromosomal disorder caused by chromosome 21 trisomy and is ihe most frequent genetic cause of intellcctual disability. The gene for thè kinesin family member 21A (KIF2JA), is a member of ihe kinesin superfamily involved in thè anterogradc fasi axonal transport. In this study, we bave evaluated thè possible differential expression of KIF2/A mRNA, by qRT-PCR, in peripheral blood leukocytes of DS subjects and it compared with thè normal population. In thè assumption that changes in KIF21A gene expression levels may affect thè axonal transport and thè development of thè nervous System of subjects with DS. In thè present case- comrol study, KIF2ÌA gene expression was increased in 72.72 % of DS samples compared with normal subjects. M. Salemi (52) • C. Romano • C. Scavuz/o • M. G. Salluzzo • P. Bosco Lahoratory of Cytogeneties. Oasi Institute for Research OD Mental Retardation and Brain Aging, Troina, Italy e-mail: msalemi@oasi.en.it; micczia@tiscali.it C. Barone • C. Romano Unir of Pediatrie» and Medicai Genetics. Oasi Institute l'or Research on Mental Retardalion and Bruiti Aging, Troina, Italy F. Ridolfo Post-graduate School in Clinical Biochemistry, University of Milan, Milan, Ilaly R. A. Cantarella ANFFAS-Caiania, Catania, Italy A. E. Calogero Scction of Endocrinology, Andrology and Internai Medicine, Depadmenl of Medicai and Pediatrie Sciences, University of Catania, Catania. Italy This finding suggests that changes in thè expression levels of KIF21A in DS subjects may affect thè axonal transport and thè development of thè nervous System. Keywords Down syndrome • KIF2IA gene • Kinesin family • qRT-PCR • mRNA expression Introduction Down syndrome (DS) is one of thè most frequent chromo- somal disorders and thè tirsi genetic cause of intellectual disability (ID). The disorder is rnainly characterized by cognitive and speech dysfunction coupled with sensory and neuromotor deh'cits. Its neuropathology highlights decreased brain size and impaired dendritic development during felal age [1]. DS can be caused by three types of chromosomal abnormalities: trisomy 21 nondisjunction, translocation, or mosaicism []]. The gene for thè kinesin family member 21A (K1F21A) (MIM ID *608283), map- ping on chromosome 12ql2, is a member of thè kinesin superfamily, a large gene family of microtubule-dependent motors with 45 members in human potentially involved in anterograde fast axonal transport [2]. Specitìcally, in mouse model, KJF2IA gene is expressed mostly in thè juvenilc brain and thè protein is present throughout thè neurons [3J. The. changes in thè expression levels of KIF2IA may affect axonal transport and thè development of thè nervous system of subjects with DS. The aim of this study was lo evaluate thè possible differential expression of KIF21A mRNA in leukocytes of peripheral blood of DS subjects compared with thè normal population and to increase thè number of patients already studied in our laboratory [4]. sy Springer