Hereditary Spastic Paraplegias (HSP) is a group of genetic disorders characterized by progressive muscle stiffness (spasticity) and progressive paralysis of the lower limbs (paraplegia) caused by degeneration of nerve cells that control muscle movement. Diagnosis can be made from infancy to the 6th decade of life, with first symptoms usually being mild gait difficulties and stiffness of the legs. These symptoms typically slowly progress so that eventually individuals with HSP may require the assistance of a cane, walker, or wheelchair.
HSP is classified clinically as “uncomplicated” (nonsyndromic or pure) or “complicated” (syndromic). Uncomplicated HSP is characterized by neurologic impairment limited to progressive lower-extremity spastic weakness, hypertonic urinary bladder disturbance, and mild diminution of lower-extremity vibration sensation. Complicated HSP forms may exhibit additional symptoms including impaired vision due to cataracts and problems with the optic nerve and retina of the eye, ataxia, epilepsy, cognitive impairment, peripheral neuropathy, and deafness.
Hereditary spastic paraplegia can be inherited in an autosomal dominant, autosomal recessive, or X-linked manner or by maternal (mitochondrial) inheritance, depending on the genetic subtype in a family. It has been linked to mutations in more than 30 genes. Autosomal dominant HSP is the most common type of HSP, found in 75%-80% of affected individuals. Mutations in SPAST (SPG4) gene account for ~45% of cases that are inherited in an autosomal dominant manner.
Analysis of 32 genes using Next Generation Sequencing technique in order to detect mutations associated to hereditary spastic paraplegia: SPG1 (L1CAM), SPG11, SPG4 (SPAST), SPG20, SPG3A (ATL1), SPG17 (BSCL2), SPG9A (ALDH18A1), SPG35 (FA2H), SPG5A(CYP7B1), SPG6 (NIPA1), SPG2 (PLP1), SPG12 (RTN2), SPG31 (REEP1), SPG10 (KIF5A), SPG50 (AP4M1), SPG51 (AP4E1), SPG47 (AP4B1), SPG52 (AP4S1), SPG15 (ZFYVE26), SPG55 (C12orf65), SPG7, SPG30 (KIF1A), SPG64 (ENTPD1), SPG42 (SLC33A1), SPG9B (ALDH18A1), SPG13 (HSPD1), SPG8 (KIAA0196), SPG18 (ERLIN2), SPG33 (ZFYVE27), SPG48 (AP5Z1), SPG43 (C19orf12), SPG39 (PNPLA6).
Sample: Peripheral blood in EDTA
Time to result: 4 weeks