what genes regulates lactase
When the lactase switch turns the lactase gene on, the lactase enzyme is produced. In babies, the lactase gene is turned on. But when babies grow into adults, the switch turns the lactase gene off in most people. In a minority of adults, a mutation in the lactase switch prevents the lactase gene from turning off.These adults are lactose tolerant. Figure 4. The genetic switch that regulates the expression of the lactase gene is active in babies but not in most human adults.nfant mammals produce the enzyme lactase in their small intestines. Lactase breaks down lactose into glucose and galactose. These two simpler sugars, or monosaccharides, are easily absorbed through the small intestine and into the bloodstream.