K. Krapfenbauer et al., Differential display reveals deteriorated mRNA levels of NADH3 (complex I)in cerebellum of patients with Down Syndrome, J NEUR TR-S, (57), 1999, pp. 211-220
Although gene hunting has been carried out in Down Syndrome (DS) cells, inf
ormation on expressional differences in DS brain is limited. We have recent
ly described expressional differences in fetal DS brain but cannot assign t
hese findings to "DS per" se or simply to "neurodegeneration".
We therefore performed gene hunting in cerebellum of adult patients with DS
and Alzheimer's disease (AD) neuropathology, AD and controls.
The gene hunting method used was differential display and pools of the indi
vidual groups were examined to rule out allelic differences.
Differential display revealed the absence of a band, identified by sequenci
ng and gene bank work as matching the NADH3 gene (99.1% identity) in cerebe
llum of DS patients. Dot blots showed the presence of NADH3 signals in only
two out of 7 DS patients.
We show at the transcriptional level that a mitochondrial enzyme, the compl
ex I, NADH3, is significantly downregulated in DS cerebellum. This extends
previous work on deficiencies of the electron transport chain in platelets
of patients with DS.