Adult-type hypolactasia and lactose malabsorption in Poland.

Abstract

The available data on the incidence of lactose malabsorption are contradictory. Potential bias in random selection is a major drawback of studies performed to-date. Moreover, molecular analysis of polymorphism -13910 C>T upstream of the lactase (LCT) gene (NM_005915.4:c.1917+326C>T; rs4988235) has not been reported in those studies. Therefore, in this study we aimed to assess genetic predisposition and clinical manifestation of adult-type hypolactasia (ATH). In two-hundred randomly chosen healthy subjects (HS) aged from 18 to 20 years, the presence of -13910 C>T polymorphic variants upstream of the LCT gene was assessed. In a subgroup of subjects with genotype predisposing to ATH, hydrogen-methane breath test (BT) with lactose loading was conducted to determine the current state of lactase activity. In addition, clinical symptoms typical for lactose malabsorption were assessed using the questionnaire method. Sixty-three out of 200 (31.5 %) HS had -13910 C/C genotype. Thus, genetically determined lactase persistence is expected in the remaining 137 (68.5 %) subjects. Thirteen out of 53 (24.5 %) HS having -13910 C/C genotype were proved to be lactose intolerant. Recalculating the data for the entire studied population it implies the incidence of lactose malabsorption in 7.7 % of subjects. Only three out of 13 (23.1 %) subjects with abnormal BT results, reported clinical symptoms related to lactose consumption. Significantly lower than previously reported incidence of clinically detectable lactose malabsorption in young healthy adults in Poland has been documented. The -13910 C/C genotype upstream of the LCT gene indicates a predisposition to ATH, but definitely does not define the current ability to tolerate lactose.

Trehalase as a possible marker of intestinal ischemia--reperfusion injury.

“…Whilst in the human population, sucrase and maltase show consistent activity that of lactase varies depending on several factors, for example the age. These facts have been confirmed by the previously undertaken studies, in which differences in lactase activity were verified while in the case of sucrase and maltase consistent values were detected (Grundmann et al, 2011;Vieira et al, 2000;Mądry et al, 2010).…”

Lactose Malabsorption and Lactose Intolerance in Children with Inflammatory Bowel Diseases

“…In several Polish studies, the incidence of the LCT-13910CC genotype associated with ATH in healthy people was estimated at 30-31.5% [7, 17], which was a comparable incidence to that obtained in the whole group of patients with IBD (31%), while slightly less than that in the group of children with AP-FGID (42.4%); the difference was not significant. In all patients, the presence of LCT-13910CC and LCT-22018GG genotypes was consistent.…”

“…In addition, it was proven that the genotypes of both variants exhibit almost complete compliance; patients with the LCT-13910CC genotype also had the LCT-22018GG genotype, and patients with the LCT-13910TT genotype has the LCT-22018AA genotype [3]. In Poland, the incidence of lactose malabsorption (LM), assessed by the hydrogen breath test, varies from 17.4 to 37.5%, while the incidence of the LCT-13910CC genotype responsible for ATH was estimated at 30-31.5% [5–7]. Typical symptoms of lactose intolerance (LI) are diarrhoea, bloating, abdominal pain, nausea, and vomiting.…”

Expression of galectin 9 mRNA in lactose maldigestion and children’s obesity

“…DISCUSSION Studies in the Caucasian populations [7,[19][20][21] showed a high correlation between lactose digestion, intestinal lactase levels, and genetic tests in individuals with different SNP MCM6 genotypes.…”