Autism Research Today is a free monthly online journal that collates and summarizes the latest research about Autism, including details on symptoms, diagnosis, treatment, causes, effects. | ||||||||
|
Real-time PCR quantitation of clostridia in feces of autistic children.Song Y, Liu C, Finegold SM Research Service, VA Medical Center West Los Angeles, Los Angeles, California 90073, USA. yulis1@yahoo.com Based on the hypothesis that intestinal clostridia play a role in late-onset autism, we have been characterizing clostridia from stools of autistic and control children. We applied the TaqMan real-time PCR procedure to detect and quantitate three Clostridium clusters and one Clostridium species, C. bolteae, in stool specimens. Group- and species-specific primers targeting the 16S rRNA genes were designed, and specificity of the primers was confirmed with DNA from related bacterial strains. In this procedure, a linear relationship exists between the threshold cycle (CT) fluorescence value and the number of bacterial cells (CFU). The assay showed high sensitivity: as few as 2 cells of members of cluster I, 6 cells of cluster XI, 4 cells of cluster XIVab, and 0.6 cell of C. bolteae could be detected per PCR. Analysis of the real-time PCR data indicated that the cell count differences between autistic and control children for C. bolteae and the following Clostridium groups were statistically significant: mean counts of C. bolteae and clusters I and XI in autistic children were 46-fold (P = 0.01), 9.0-fold (P = 0.014), and 3.5-fold (P = 0.004) greater than those in control children, respectively, but not for cluster XIVab (2.6 x 10(8) CFU/g in autistic children and 4.8 x 10(8) CFU/g in controls; respectively). More subjects need to be studied. The assay is a rapid and reliable method, and it should have great potential for quantitation of other bacteria in the intestinal tract. Published 5 November 2004 in Appl Environ Microbiol, 70(11): 6459-65.
© 2004-2008 Autism Research Today. All Rights Reserved. |
| ||||||
