This gene on chromosome 2 codes for the enzyme lactase.This enzyme enables infants to break down lactose, the main sugar in milk. the gene is turned off after infancy, making the digestion of dairy products difficult and painful.
The LCT gene provides instructions for making an enzyme called lactase. This enzyme helps to digest lactose, a sugar found in milk and other dairy products. Lactase is produced by cells that line the walls of the small intestine. At least nine LCT gene mutations cause congenital lactase deficiency, also called congenital alactasia. In this disorder, infants are unable to break down lactose (lactose intolerance) in breast milk or formula. This involves a molecular mechanism in which the gene for lactase, needed for digesting milk, is turned off at the end of the weaning period. Lactase is an enzyme needed for the metabolism of the lactose sugar found in milk. So while young mammals are able to digest milk from the mother they will reach a stage shortly after weaning when the consumption of milk will incur abdominal cramps and diarrhoea. Causes of lactose intolerance. Lactose is broken down by lactase. Lactose is a sugar that occurs naturally in milk and most dairy products. Lactose is readily broken down in the gut by an enzyme called lactase. Babies produce large amounts of lactase until they are weaned. Lactose intolerance is a recessive disorder. For a recessive disorder to show, both copies of the gene, called alleles, have to be identical. Individuals who have a cytosine (C) residue on both alleles close to the lactase gene do not produce lactase in adulthood and are lactose intolerant. lactose intolerance-caused by mutations in the LCT gene. At least nine LCT gene mutations cause congenital lactase deficiency, also called congenital alactasia. In this disorder, infants are unable to break down lactose (lactose intolerance) in breast milk or formula. The LCT gene mutations change single protein building blocks (amino acids) in the lactase enzyme or result in an enzyme that is abnormally short Lactose intolerance is the inability of adults and children to digest lactose, a sugar found in milk and to a lesser extent dairy products, causing side effects. It is due to a lactase deficiency, or hypolactasia. Lactose intolerance is distinct from milk allergy, an immune response to cow's milk proteins. They may be distinguished in diagnosis by giving lactose-free milk, producing no symptoms in the case of lactose intolerance, but the same reaction as to normal milk in the presence of a milk allergy. Lactose intolerance is not an allergy, because it is not an immune response, but rather a sensitivity to dairy caused by lactase deficiency. Milk allergy, occurring in only 4% of the population, is a separate condition, with distinct symptoms that occur when the presence of milk proteins trigger an immune reaction. Lactose intolerance is distinct from milk allergy, an immune response to cow's milk proteins. They may be distinguished in diagnosis by giving lactose-free milk, producing no symptoms in the case of lactose intolerance, but the same reaction as to normal milk in the presence of a milk allergy. Lactose intolerance is the decreased ability to digest lactose, a type of sugar found in the milk of mammals such as cows and goats as well as in human breast milk. It is also an ingredient in other dairy products such as cheese, cottage cheese, yoghurt, ice cream, and butter. Mutations of the LCT gene result in congenital lactase deficiency and are an autosomal recessive inheritance, thus requiring one mutated gene from each parent. This is a rare form of lactose intolerance that begins at birth and severely inhibits a baby's ability to digest milk or milk-based formulas. This gene on chromosome 2 codes for the enzyme lactase. This enzyme enables infants to break down lactose, the main sugar in milk. In people who are lactose tolerant, the gene remains active throughout their lives. In most people who are lactose intolerant, the gene is turned off after infancy, making the digestion of dairy products difficult and painful. 1 Primary lactose intolerance: the is the common form of lactose intolerance in which lactase gene expression turns off in childhood, and the individual is relatively lactase deficient as a teenager and adult. Lactose persistence, and therefore lactose tolerance, are inherited as a dominant trait. Lactose intolerance is the result of being homozygous for the recessive lactase allele that is poorly expressed after early childhood.
http://ghr.nlm.nih.gov/gene/LCT http://powerofthegene.com/joomla/index.php/genetically-inherited-diseases/metabolic-disorders/lactose-intolerance http://biotechlearn.org.nz/themes/food_intolerance_and_allergies/genes_and_lactose_intolerance http://ghr.nlm.nih.gov/gene/LCT https://en.wikipedia.org/wiki/Lactose_intolerance https://en.wikipedia.org/wiki/Lactose_intolerance https://labtestsonline.org/understanding/conditions/lactose-intolerance https://www.dnalc.org/view/15953-What-is-lactose-tolerance-intolerance-.html http://www.vivo.colostate.edu/hbooks/pathphys/digestion/smallgut/lactose_intol.html
what chromosome is lactose intolerance on