DECREASED SENSITIVITY TO NERVE GROWTH-FACTOR OF DORSAL-ROOT GANGLION NEURONS CULTURED FROM MOUSE TRISOMY-16, A MODEL OF DOWNS-SYNDROME

The effect of NGF was studied on the adhesion of mouse dorsal root ganglion (DRG) neurons to a laminin-coated surface and on their subsequent survival in primary culture. DRG neurons were obtained both from normal diploid mice and trisomy 16 mice. The latter are considered a model of human trisomy 21, Down's syndrome. Whereas both diploid and trisomy DRG neurons depended on NGF for adhesion, the sensitivity of trisomy 16 neurons to NGF was significantly reduced (P < 0.05). This suggests that excess expression of genes on mouse chromosome 16 alters NGF-regulated adhesion to laminin. Survival of neurons that had attached to laminin in culture did not appear dependent on NGF for either diploid or trisomy 16 neurons.