23.01.2005, 12:52
in Bezug auf LI scheint 1965 "stehen geblieben" zu sein:
Alternative titles; symbols
DISACCHARIDE INTOLERANCE III
ADULT LACTASE DEFICIENCY
LACTOSE INTOLERANCE
LACTASE NONPERSISTENCE
LACTASE PERSISTENCE, INCLUDED
HEREDITARY PERSISTENCE OF INTESTINAL LACTASE, INCLUDED
LACTASE RESTRICTION, INCLUDED
Gene map locus 2q21
TEXT
A number sign (#) is used with this entry because of evidence that the disorder is associated with noncoding variation in the MCM6 gene (601806).
Cuatrecasas et al. (1965 ) found that 3 of 19 whites and 11 of 42 blacks had deficient absorption of lactose. Because of a strong correlation with low milk consumption, they concluded that lactose intolerance is an acquired trait . Loss of symptoms with prolonged lactose intake and decreased absorption with milk restriction seemed to support this conclusion. They noted that 'genetic polymorphism is not, however, excluded.' That adult lactose intolerance and the deficiency of intestinal lactase that underlies it is a genetic polymorphism was strongly indicated by the study of Bayless and Rosensweig (1966, 1967) in 20 black and 20 white nonpatient volunteers from a penal institution. They demonstrated that low levels of intestinal lactase activity correlated well with a history of milk intolerance which usually had begun during or after adolescence. They concluded that lactose tolerance/intolerance is a genetic polymorphism like colorblindness and ABO blood type. Studies in groups around the world confirmed that adult lactase deficiency is a racial characteristic. Family studies showed that it is an autosomal recessive trait. In most tropical and in all subtropical countries and East Asian populations, lactase deficiency is an inappropriate term for a trait that is present in most adult humans. Both high and low lactase activity in healthy adult humans is normal; thus, hereditary persistence of intestinal lactase is a more appropriate designation.
Isolated lactase deficiency of adulthood was found to be more frequent in the American Indian than in Caucasians (Welsh et al., 1967). Lactose intolerance is also present in a great majority of adult Orientals (Huang and Bayless, 1968). Cook (1967) found that in Africans the deficiency developed in the first 4 years and sometimes in the first 6 months. Rosensweig et al. (1967) found 3 groups defined by lactase level and suggested that these correspond to the genotypes in a diallelic system. Some heterozygotes in their classification had milk- and lactose-induced symptoms.
Die Entwicklung weiter:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=OMIM&dopt=Detailed&tmpl=dispomimTemplate&list_uids=223100
Uli
Alternative titles; symbols
DISACCHARIDE INTOLERANCE III
ADULT LACTASE DEFICIENCY
LACTOSE INTOLERANCE
LACTASE NONPERSISTENCE
LACTASE PERSISTENCE, INCLUDED
HEREDITARY PERSISTENCE OF INTESTINAL LACTASE, INCLUDED
LACTASE RESTRICTION, INCLUDED
Gene map locus 2q21
TEXT
A number sign (#) is used with this entry because of evidence that the disorder is associated with noncoding variation in the MCM6 gene (601806).
Cuatrecasas et al. (1965 ) found that 3 of 19 whites and 11 of 42 blacks had deficient absorption of lactose. Because of a strong correlation with low milk consumption, they concluded that lactose intolerance is an acquired trait . Loss of symptoms with prolonged lactose intake and decreased absorption with milk restriction seemed to support this conclusion. They noted that 'genetic polymorphism is not, however, excluded.' That adult lactose intolerance and the deficiency of intestinal lactase that underlies it is a genetic polymorphism was strongly indicated by the study of Bayless and Rosensweig (1966, 1967) in 20 black and 20 white nonpatient volunteers from a penal institution. They demonstrated that low levels of intestinal lactase activity correlated well with a history of milk intolerance which usually had begun during or after adolescence. They concluded that lactose tolerance/intolerance is a genetic polymorphism like colorblindness and ABO blood type. Studies in groups around the world confirmed that adult lactase deficiency is a racial characteristic. Family studies showed that it is an autosomal recessive trait. In most tropical and in all subtropical countries and East Asian populations, lactase deficiency is an inappropriate term for a trait that is present in most adult humans. Both high and low lactase activity in healthy adult humans is normal; thus, hereditary persistence of intestinal lactase is a more appropriate designation.
Isolated lactase deficiency of adulthood was found to be more frequent in the American Indian than in Caucasians (Welsh et al., 1967). Lactose intolerance is also present in a great majority of adult Orientals (Huang and Bayless, 1968). Cook (1967) found that in Africans the deficiency developed in the first 4 years and sometimes in the first 6 months. Rosensweig et al. (1967) found 3 groups defined by lactase level and suggested that these correspond to the genotypes in a diallelic system. Some heterozygotes in their classification had milk- and lactose-induced symptoms.
Die Entwicklung weiter:
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=OMIM&dopt=Detailed&tmpl=dispomimTemplate&list_uids=223100
Uli