Mental deficiency in three families with SPG4 spastic paraplegia

Eur J Hum Genet. 2008 Jan;16(1):97-104. doi: 10.1038/sj.ejhg.5201922. Epub 2007 Oct 24.

Abstract

Mutations and deletions in the SPG4 gene are responsible for up to 40% of autosomal dominant hereditary spastic paraplegia (HSP). Patients have pyramidal signs in the lower limbs and some present additional features including cognitive impairment such as executive dysfunction or subcortical dementia. We report 13 patients from three SPG4 families, who had spastic paraplegia associated with mental retardation (n=1), extensive social dependence (n=10), or isolated psychomotor delay (n=2). In family FSP-698, 10 affected individuals had both HSP and mental deficiency leading to social dependence in 9 and institutionalization in 5. The mean age at onset of spastic paraplegia was 11+/-20 years, ranging from 1 to 51 years. This phenotype segregated either with a novel p.Glu442Lys mutation or the two previously described p.Arg459Thr and p.Arg499Cys substitutions in the SPG4 gene. Since two of these mutations were previously reported in families with a pure form of the disease, another genetic factor linked to SPG4 could be responsible for this complex phenotype.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / genetics*
  • Adult
  • Amino Acid Substitution
  • Female
  • Genes, Dominant
  • Haplotypes
  • Humans
  • Intellectual Disability / complications
  • Intellectual Disability / genetics*
  • Male
  • Middle Aged
  • Mutation*
  • Mutation, Missense
  • Pedigree
  • Phenotype
  • Point Mutation
  • Spastic Paraplegia, Hereditary / complications
  • Spastic Paraplegia, Hereditary / genetics*
  • Spastic Paraplegia, Hereditary / physiopathology
  • Spastic Paraplegia, Hereditary / psychology
  • Spastin

Substances

  • Adenosine Triphosphatases
  • Spastin
  • SPAST protein, human