Article Text

Download PDFPDF
Recessive spastic paraparesis associated with complex I deficiency due to MTHFR mutations
  1. Deborah Bathgate1,
  2. Patrick Yu-Wai-Man2,
  3. Brian Webb3,
  4. Robert W Taylor2,
  5. Brian Fowler4,
  6. Patrick F Chinnery2
  1. 1Department of Neurology, James Cook University Hospital, Middlesbrough, UK
  2. 2Mitochondrial Research Group, Institute of Human Genetics, Newcastle University, Newcastle upon Tyne, UK
  3. 3Department of Biochemistry, James Cook University Hospital, Middlesbrough, UK
  4. 4University Children's Hospital (UKBB), Basel, Switzerland
  1. Correspondence to Professor P F Chinnery, Institute of Human Genetics, Central Parkway, Newcastle upon Tyne NE1 3BZ, UK; p.f.chinnery{at}

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

5,10-Methylenetetrahydrofolate reductase (MTHFR, EC. catalyses the reduction of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. This serves as a methyl donor for homocysteine re-methylation to methionine, which is essential for DNA and protein methylation, neurotransmitter and phospholipid synthesis. Homocystinuria due to MTHFR deficiency usually presents in childhood with developmental delay, psychiatric features, and an encephalopathy with low or normal plasma methionine.1 Onset in late childhood or early adult life is rare.1 Here we describe MTHFR deficiency presenting in two adult siblings with slowly progressive spastic paraparesis.

Case report

A young adult of Pakistani origin presented with a 2 year history of walking difficulty due to a spastic paraparesis. Brain and spinal cord MR imaging was normal, as were electromyography, nerve conduction studies, and visual evoked potentials. Routine haematological and biochemical blood tests were normal, as were levels of vitamin B12, folate, very long chain fatty acids, hexosaminidase, copper, and HTLV1 antibodies. The parents were first cousins, leading to a clinical diagnosis of autosomal recessive hereditary spastic paraparesis (HSP).

Five years later the patient presented acutely with a behavioural disturbance, urinary and faecal …

View Full Text


  • Funding PFC is a Wellcome Trust Senior Fellow in Clinical Science who also receives funding from the Medical Research Council (UK), the UK Parkinson's Disease Society, and the UK NIHR Biomedical Research Centre for Ageing and Age Related Disease Award to the Newcastle upon Tyne Foundation Hospitals NHS Trust. RWT is supported by the UK National Commissioning Group for Rare Mitochondrial Disorders of Adults and Children. PYWM is an MRC (UK) Clinical Research Fellow.

  • Competing interests None.

  • Patient consent Obtained.

  • Provenance and peer review Not commissioned; externally peer reviewed.