Hereditary spastic paraplegias have a heterogeneous genetic etiology. While ~50% of all patients of dominant HSP are explained by three major genes (spastin, atlastin, REEP1), the remaining genetic causes are rare and explain no more then another 15% of patients. For recessive HSP only about 40-50% of patients receive a genetic diagnosis. Recent progress is tremendous and will likely identify the genetic basis for another 20% of patients in the coming five years. Especially interesting is that less than 50% of cases are clarified in select exome sequencing approaches, implaying that whole genome studies will be necessary. In addition, HSPs often show clinical overlap with related neurological diseases, such as ataxias, leukodystrophies, metabolic disorders, and mitochondrial disorders. Thus, there is a two-fold need: 1) to standardize the clinical classification in a collaborative fashion and 2) to expand the knowledge of underlying causative genes and molecular pathways. This will be beneficial beyond HSP and contribute to our understanding of a number of related neurological diseases. For this study, we will create a collaborative structure between investigators in the USA, Germany, France, Belgium, Brazil, Austarlia, and indirectly Middle East and Northern Africa. We will be able to systematically study THE largest clinical sample of HSP in the world led by world-renowned clinical and genetic experts. Importantly, existing genomic data will be contributed in kind by our collaborators and jointly used in the analysis. Our recent success in identifying dozens of genes for familial neurological disorders, including HSP validates the suggested approach. Data will be shared with dbGAP. We expect to identify and publish 2 ? 4 novel genes per year and create a lasting resource of clinical and genomic data.

Public Health Relevance

Hereditary spastic paraplegias (HSP) are inherited disorder of long central axons in the corticospinal tracts. More than half of all affected families currently remain without a definite diagnosis because the underlying genetic factors that cause their disease have not been identified yet. Our study aims to use expert exome sequencing and, for the first time in this area, whole genome sequencing to identify these unknown HSP genes. This will ultimately allow to devise strategies to treat these diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
2R01NS072248-06A1
Application #
9239137
Study Section
Genetics of Health and Disease Study Section (GHD)
Program Officer
Gubitz, Amelie
Project Start
2011-02-01
Project End
2021-07-31
Budget Start
2016-09-15
Budget End
2017-07-31
Support Year
6
Fiscal Year
2016
Total Cost
Indirect Cost
Name
University of Miami School of Medicine
Department
Genetics
Type
Schools of Medicine
DUNS #
052780918
City
Coral Gables
State
FL
Country
United States
Zip Code
33146
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