Clinical and molecular characterization of hereditary spastic paraplegia in a spanish Southern region.

INTRODUCTION: Spastic paraplegia (SPG) is a syndrome characterised by lower limb spasticity, occurring alone or in association with other neurological manifestations. Despite of the new molecular technologies, many patients remain yet undiagnosed. OBJECTIVE: The purpose of this study was to describe the clinical presentation and molecular characteristics of a cohort of 27 patients from 18 different families with SPG in the south of Spain. METHODS: We used a targeted next-generation sequencing (NGS) approach to study a proband from each family. RESULTS: Variants in SPG11 gene were the most common cause of SPG in our area. We made a genetic diagnosis in 52% of cases, identified 3 novel variants and reclassified one uncertain variant in SPG11 gene as pathogenic variant. We identified a patient with two truncanting mutations in SPG11 gene and late onset disease and report another missense mutation outside of motor domain of KIF1A gene in a family with pure SPG. CONCLUSION: Our study contributes to enhance the scientific knowledge of SPG. It is important to note the large group of cases (48%) that were not genetically diagnosed in our cohort. Therefore NGS approach is an efficient diagnostic tool, but it still large the number of non-diagnosed subjects, suggesting further genetic heterogeneity.

The role of CDKN2A/B deletions in pediatric acute lymphoblastic leukemia.

The CDKN2A/B genes in the 9p21 chromosomal region are frequently involved in human cancer, including pediatric acute lymphoblastic leukemia (ALL). These genes encode 3 proteins that belong to the RB1 and TP53 pathways and act as tumor suppressors by regulating the G1/S checkpoint of the cell cycle. The prognostic value of deletions in the CDKN2A/B locus in ALL is controversial in part due to the limitations of the methodologies used. Further studies with advanced technologies are needed for elucidation. Future studies would also highlight whether CDK4/CDK6 selective inhibitors might be useful therapies for children with these genetic aberrations.