Decreased numbers of motor neurons in humans with DS.

<p>(<b>a</b>) Examples of human cervical spinal cord sections stained with Luxol Fast Blue. Dashed white circle indicates area containing motor neurons. Inset shows a higher magnification image of the ventral area containing motor neurons. Scale bar, 100 μm. (<b>b</b>) Number of motor neurons per hemisection of cervical spinal cord of adults with DS, ALS and controls (n = 4 control, 3 DS, 3 ALS). All graphs show mean±SEM. Data analyzed with unpaired t-test, **p < 0.01, ***p < 0.001.