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Adult-type hypolactasia results from the progressive decline of lactase-phlorizin hydrolase activity in enterocytes after weaning. Lactase nonpersistence may determine a primary lactose intolerance with reduced diary product consumption, which is possibly related to an increased risk of colon cancer. Recently, a genetic variant C/T–13910upstream of the lactase-phlorizin hydrolase (LCT) gene has been strongly correlated with the lactase persistence/nonpersistence trait in both family and case-control studies. The authors validate a denaturing high-performance liquid chromatography (dHPLC)–based assay versus conventional genotype sequencing in detecting the C/T–13910polymorphism of LCTand evaluate its prevalence in 2 different Italian geographical areas and in colorectal cancer patients. DNA samples of 157 healthy subjects and 124 colon cancer patients from Apulia and of 97 healthy subjects from Sardinia were evaluated for the C/T–13910polymorphism by dHPLC, sequencing, and restriction fragment length polymorphism (RFLP). Under optimized conditions, dHPLC was as sensitive as DNA sequencing and detected a new genetic variant (T/C-13913) in 2 individuals that was not identified by RFLP assay. Frequency of lactase non-persistence genotype (C/C–13910) was similar in healthy subjects from 2 different Italian geographical areas and not increased in patients with colorectal cancer. The results indicate that the dHPLC method may be used as a rapid, noninvasive, and laborsaving screening tool for genotyping C/T–13910polymorphism, with high success, low cost, and reproducibility.

There is recent evidence that upper-gut motor abnormalities may be present in coeliac disease. However, to date, the pathophysiological mechanisms responsible for the above have not been explored. The purpose of the present study was to investigate upper-gut motor activity in coeliac disease and explore the role played by the autonomic nervous system in motility disturbances. Thirty untreated adult coeliac patients were recruited into the study. Oesophageal manometry and cardiovascular autonomic tests were performed in all patients; oesophageal pH-metry was carried out in 20 patients, gastrointestinal manometry in eight and scintigraphic gastric emptying in 13. Oesophageal motor abnormalities were detected in about 50% of patients, pH-metry was abnormal in 30% of them, and up to 75% of coeliac patients displayed gastrointestinal motility alterations. Delayed gastric emptying was documented in about 50% of patients and was correlated with manometric post-prandial hypomotility. Autonomic tests were positive in 45% of patients as a group, and reached pathological score in 19% of them. Autonomic score correlated significantly with the percentage of bi-peaked waves and with the number of fasting intestinal clusters. This study confirms that upper-gut motor abnormalities are frequently present in adult coeliac disease. Extrinsec autonomic neuropathy may play a role, although other pathophysiological mechanisms are likely to occur.