title: The frequency distribution of lactose malabsorption among adult populations from the eastern and western Egyptian deserts.
abstract: The study consisted of 172 subjects belonging to ethnic groups from Sinai in the Eastern Desert and the New Valley in the Western Desert, with respective mean ages of 36.7 +/- 2.0 and 26.6 +/- 1.0 years. Lactose absorption was assessed by measurement of urinary galactose in pooled 2-hr urine samples following ingestion of an oral lactose dose of 40 g. Mean 2-hr excretion values after ingestion were 32.3 mg galactose in the Sinai and 7.7 mg in the New Valley. In the evaluation of lactose malabsorption, a diagnosis of lactose malabsorption is based upon a cutoff point of 0.075 mg/mg urinary galactose:creatinine ratio. The overall prevalence rate in those populations is 34.3%. The proportion of lactose malabsorbers was 11.1% in Sinai and 51.0% in the New Valley. Highly significant differences (chi 2 = 29.5, P < 0.0001) were found between the two ethnic groups with regard to the frequency distribution of lactose malabsorption. The existence of an east-west gradient of increasing frequencies of lactose malabsorption gene is suggested.
authors.affiliation: Department of Nutrition, National Research Center, Giza, Dokki, Egypt.
authors.forename: L
authors.initials: L
authors.lastname: Hussein
authors.forename: A
authors.initials: A
authors.lastname: Ezzilarab
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003404:Creatinine / Q000652:urine; D003889:Desert Climate; D004534:Egypt / Q000453:epidemiology; D005260:Female; D005690:Galactose / Q000652:urine; D006801:Humans; D007785:Lactose / Q000008:administration & dosage / Q000378:metabolism*; D007787:Lactose Intolerance / Q000208:ethnology* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D003404:Creatinine; D001616:beta-Galactosidase; D007785:Lactose; D005690:Galactose