TREH (Trehalase): TREH is a gene that encodes the enzyme trehalase, which is involved in the breakdown of trehalose, a disaccharide sugar. Trehalase plays a crucial role in carbohydrate metabolism, particularly in the gut where trehalose is hydrolysed. Deficiencies in trehalase activity can lead to trehalose intolerance, causing gastrointestinal symptoms following the consumption of trehalose.