Biochemical anomalies in people with a visual sub-type of dyslexia

Visual processing problems in people with dyslexia are now well recognised, with increasing evidence to suggest that such problems may be linked to anomalies in the metabolism of essential fatty acids. This paper reports an analysis of differences in amino acid excretion and plasma lipids for people with a visual processing sub-type of dyslexia. The study involved two experimental sub-groups, an adult group and a juvenile group, and age- and sex-matched controls. Significant differences were found between experimental and control groups in plasma cholesterol levels and in a saturated odd-chain fatty acid, heptadecaenoic acid. The incorporation of heptadecanoic acid into cell membrane phospholipids, with resultant changes in membrane lipid composition, would have implications for altered membrane function and neurotransmission. There were also lower mean levels in most n-3 and n-6 essential fatty acids for the experimental group. In addition, significant differences were found in plasma serine levels, serine is a component of cell membrane phospholipids and has implications for neural functioning. The identified differences in heptadecaenoic acid and cholesterol may point to altered gastrointestinal absorption or to the presence of a chronic viral or bacterial infection. Studies have reported an association between immune disorders and dyslexia, with viral infection claimed to influence the incorporation of fatty acids into cell membranes. There is also a high familial incidence of visual dyslexia, which raises the possibility of familial transfer of infectious agents. Dietary intervention, targeting specific biochemical anomalies may provide an effective treatment