Conversely, a decrease in enzymes involved in the digestion of nutrients – especially lactase – is frequently observed in acute and chronic enteropathies.37,38 The inherited sucrase-isomaltase (SI) deficiency leads to sucrose malabsorption causing diarrhoea and abdominal cramps.39 Accordingly, it should generally be advantageous to increase the concentration of digestive enzymes within the BBM (measured as an increase in enzyme activity per gram of total protein) – as well as the rate of nutrient uptake, to counteract diarrhoea. The gene discussed is LCT; the disease is Diarrhea.