Dosage effect of SOD-A gene in 21-trisomic cells

SOD-A activity was measured by the polarographic method of catalytic currents in 30 subjects 10-24 years of age with a karyotype 47, + 21, and 30 age matched normal subjects. The ratio of the average amount of SOD-A in 21-trisomic cells to the average amount in normal cells is 1.4495. Statistical analysis confirms that this ratio does not differ significantly from the ratio 1.5 expected in the case of a simple gene dosage effect.