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Cavichio MWE, Quaio CRDC, Baratela WADR, Oliveira PMCD, Tahan S. EVALUATION OF AGREEMENT BETWEEN C/T-13910 POLYMORPHISM GENOTYPING RESULTS AND LACTOSE TOLERANCE TEST RESULTS: A RETROSPECTIVE POPULATION-BASED STUDY IN BRAZIL. ARQUIVOS DE GASTROENTEROLOGIA 2024; 61:e23104. [PMID: 38451663 DOI: 10.1590/s0004-2803.24612023-104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/28/2023] [Indexed: 03/08/2024]
Abstract
BACKGROUND Lactose tolerant test (LTT) is the most broadly used diagnostic test for lactose intolerance in Brazil, is an indirect, minimally invasive and a low-cost test that is widely available in primary care and useful in clinical practice. The C/T-13910 polymorphism in lactase persistence has been well characterized in Caucasian populations, but there are no studies evaluating the concordance between C/T-13910 polymorphism genotyping results and LTT results in Brazil, where the population is highly mixed. OBJECTIVE We aimed to evaluate agreement between presence of C/T-13910 polymorphism genotyping and malabsorption in LTT results. METHODS This is a retrospective analysis of a Brazilian population whose data were collected from a single laboratory database present in several Brazilian states. Results of individuals who underwent both genetic testing for lactose intolerance (C/T-13910 polymorphism genotyping) and an LTT from April 2016 until February 2019 were analysed to evaluate agreement between tests. Groups were classified according to age (<10-year-old (yo), 10-17 yo, ≥18 yo groups) and state of residence (São Paulo or Rio Grande do Sul). Results: Among the 404 patients evaluated, there was agreement between the genotyping and LTT results in 325 (80.4%) patients and discordance in 79 (19.6%) patients (k=0.42 -moderate agreement). Regarding the genotype, 47 patients with genotype C/C (lactase nonpersistence) had normal LTT results, and 32 with genotype C/T or T/T (indicating lactase persistence) had abnormal LTT results. Neither age nor state of residence (Rio Grande do Sul or São Paulo) affected the agreement between test results. CONCLUSION Considering the moderate agreement between C/T-13910 polymorphism genotyping and LTT results (κ=0.42) in the Brazilian population, we hypothesize that an analysis of other polymorphisms could be a strategy to improve the agreement between genotyping and established tests and suggest that additional studies should focus on exploring this approach. BACKGROUND • Lactose intolerance is highly prevalent and may be implicated as a cofactor, or as a differential diagnosis, in many gastrointestinal conditions. BACKGROUND • The C/T-13910 polymorphism in lactase persistence is well characterized in Caucasian populations for lactase persistence. BACKGROUND • Concordance between genotyping and functional tests does not occur in all patients. BACKGROUND • Brazil has a highly mixed population and knowledge regarding presence of other polymorphisms is of importance in clarifying difficult cases.
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Affiliation(s)
| | | | | | | | - Soraia Tahan
- Grupo Fleury, Departamento de Gastroenterologia, São Paulo, SP, Brasil
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Subjective, but not documented, lactose intolerance accompanies irritable bowel syndrome. POSTEP HIG MED DOSW 2022. [DOI: 10.2478/ahem-2022-0027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Introduction
Lactose intolerance, due to lactase deficiency, may overlap with the symptoms of irritable bowel syndrome (IBS) or lead to an incorrect diagnosis of IBS. Identification of lactose intolerance and lactase deficiency enables targeted treatment to be implemented.
The aim of the study was to search for a frequency of a lactose intolerance symptoms in patients with IBS, depending on the results of hydrogen breath test (HBT).
Materials and Methods
The study involved 56 patients with IBS and 23 healthy people. Both, IBS patients and healthy controls, were asked to complete a survey about IBS symptoms and tolerance of lactose-containing products. A HBT was performed on all subjects.
Results
Lactase deficiency was diagnosed in 60.7% of patients with IBS and 43.5% of control group. The differences between the study groups were not statistically significant. No statistically significant differences were observed between the incidence of lactase deficiency depending on the type of IBS.
In the group of patients with IBS and normal HBT results, as well as in patients with IBS and lactase deficiency, there were no statistically significant differences in the frequency of lactose intolerance symptoms. However, among people with normal HBT results, patients with IBS reported symptoms of intolerance after consuming lactose-containing foods significantly more often compared to the control group (p<0.05).
Conclusions
Frequency of lactase deficiency does not differ between IBS patients and healthy individuals. Patients with IBS are more likely to report symptoms of lactose intolerance, regardless of the HBT result, compared to healthy individuals.
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3
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Horne JR, Nielsen DE, Madill J, Robitaille J, Vohl MC, Mutch DM. Guiding Global Best Practice in Personalized Nutrition Based on Genetics: The Development of a Nutrigenomics Care Map. J Acad Nutr Diet 2021; 122:259-269. [PMID: 33744236 DOI: 10.1016/j.jand.2021.02.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 01/29/2021] [Accepted: 02/05/2021] [Indexed: 12/13/2022]
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Silva CDJ, Leite IDS, Rodrigues JW, Almeida SPD, Nóbrega BP, Sampaio Filho JDR. ANALYSIS OF LACTOSE INTOLERANCE IN STUDENTS WITH SUGGESTIVE SYMPTOMS OF IRRITABLE BOWEL SYNDROME. ARQUIVOS DE GASTROENTEROLOGIA 2019; 56:304-311. [PMID: 31633730 DOI: 10.1590/s0004-2803.201900000-57] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 07/05/2019] [Indexed: 11/21/2022]
Abstract
BACKGROUND Irritable bowel syndrome is a clinical condition presenting pain, distension and abdominal fullness, diarrhea, constipation, and other symptoms. It generates significant impacts on the quality of life of those affected. The pathophysiology is uncertain, but the role of various food types has been established in bowel sensitivity and its clinical manifestations. Carbohydrate intolerance, particularly to lactose, generates similar and sometimes indistinguishable symptoms from irritable bowel syndrome, and in clinical practice is both a frequent and underdiagnosed condition. Carbohydrate intolerance is related to enzymatic deficiencies, alterations of intestinal microbiota and even genetic change. The principal test for a diagnosis of lactose intolerance is the breath test, which measures hydrogen emission (produced only by bacteria), after ingestion of the corresponding substrate. OBJECTIVE The present work aims to verify the prevalence of lactose intolerance in university students, presenting gastrointestinal symptoms suggestive of irritable bowel syndrome. METHODS In a transversal study, to screen for those with suggestive symptoms, 124 medicine students participated by responding to a form. Those with abdominal pain were referred for anti-parasite treatment in order to exclude intestinal parasites as a secondary cause. Subsequently, using the hydrogen breath test, bacterial overgrowth was investigated, and if negative, lactose intolerance testing would be performed. Patients presenting high hydrogen concentrations of ≥20 ppm above the basal level were considered lactose intolerant. RESULTS Of the total of students researched (n=124), 7 were excluded because they did not completing all study phases. From those 117 individuals effectively included in the survey; 8 (6.8%) were diagnosed with lactose intolerance and 2 (1.7%) with bacterial overgrowth. Intolerance was more frequent in; female individuals (75%), age range 18 to 25 years (62.5%), being colored (50%), and in their 5th semester of studies (37.5%). The presence of at least one gastrointestinal symptom among those presenting intolerance (100%), and those not presenting intolerance (42.2%) was found (P=0.002). In addition to abdominal pain (100%) (P<0.001), the most recurrent gastrointestinal symptom in the lactose intolerant students was the distension/flatulence (62.5%) (P=0.026). In relation to life habits and food patterns, there was no statistical difference between lactose tolerant and intolerant individuals, or for symptom frequencies. The more advanced students, completing more periods towards graduation, demonstrated more occurrences of gastrointestinal symptoms, yet without presenting significant statistical discrepancies. CONCLUSION In view of the test sample quantity (n=21), a high prevalence of lactose intolerance (6.8%) in the academic environment, with epidemiological characteristics compatible to those found the literature is demonstrated, generating knowledge with understanding to prevent, diagnose, alleviate and treat lactose intolerant university students, and generate positive impacts towards well-being, improving the quality of life of these individuals.
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Affiliation(s)
- Cleise de Jesus Silva
- Faculdade de Medicina da Universidade Federal Do Vale do São Francisco, Paulo Afonso, BA, Brasil
| | | | - José Weberton Rodrigues
- Faculdade de Medicina da Universidade Federal Do Vale do São Francisco, Paulo Afonso, BA, Brasil
| | | | - Bruna Pessoa Nóbrega
- Faculdade de Medicina da Universidade Federal Do Vale do São Francisco, Paulo Afonso, BA, Brasil
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Araujo EM, Dos Santos L, Coutinho R, Assis V, Brandão N, Almeida D, Conceição G, Figueredo C, Fonseca H, Lima MDL, Lemaire D, Rios D. Genetic and Oral Tests for the Diagnosis of Lactose Intolerance in Mixed-Ancestry Brazilians with Metabolic Syndrome. Lifestyle Genom 2019; 12:1-9. [PMID: 31352438 DOI: 10.1159/000501690] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 06/21/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS Metabolic syndrome (MetS) comprises a cluster of physiological and anthropometric abnormalities. MetS has been linked to lactose intolerance (LI). The aim of this study was to compare the sensitivity and specificity to detect LI using 2 different tests: (1) a genetic test and (2) an oral lactose tolerance test (OLTT). METHODS Two hundred and fifty-four MetS patients, ≥20 years of age, of both genders, were recruited for this comparative study. Nine single nucleotide polymorphisms (SNPs) were selected for genetic investigation: rs182549and rs4988235(both considered "gold standard"); rs56064699; rs148142676; rs562211644; rs59533246; rs3754689; rs2278544,and rs10552864(as potential novel SNPs). Sensitivity and specificity, as well as positive and negative predictive values, were calculated for each genotype using WINPEPI version 11.65. Differences between positive and negative OLTT groups were considered statistically significant when p ≤ 0.05. RESULTS Among the selected SNPs, only rs182549(p < 0.001) and rs4988235(p < 0.001) gave similar results compared to an OLTT. The sensitivity of both SNPs to detect LI was 87 and 86%, and specificity was 83 and 82.5%, respectively. CONCLUSION Genetic tests using rs182549and rs4988235SNPs showed high agreement with OLTT. These genetic tests may be a good option to replace OLTT in MetS patients.
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Affiliation(s)
- Edilene Maria Araujo
- Nucleus of Research and Extension in Nutritional Genomics and Metabolic Dysfunctions (GENUT), Life Sciences Department (DCV), University of the State of Bahia (UNEB), Salvador, Brazil, .,Posgraduate Program in Biotechnology (PPGBiotec), State University of Feira de Santana (UEFS), Salvador, Brazil, .,Interactive Process of Organs and Systems (PPGorgsystem), Health Sciences Institute, Federal University of Bahia, Salvador, Brazil,
| | - Luama Dos Santos
- Nucleus of Research and Extension in Nutritional Genomics and Metabolic Dysfunctions (GENUT), Life Sciences Department (DCV), University of the State of Bahia (UNEB), Salvador, Brazil.,Interactive Process of Organs and Systems (PPGorgsystem), Health Sciences Institute, Federal University of Bahia, Salvador, Brazil
| | - Radamés Coutinho
- Nucleus of Research and Extension in Nutritional Genomics and Metabolic Dysfunctions (GENUT), Life Sciences Department (DCV), University of the State of Bahia (UNEB), Salvador, Brazil.,Interactive Process of Organs and Systems (PPGorgsystem), Health Sciences Institute, Federal University of Bahia, Salvador, Brazil
| | - Viviane Assis
- Nucleus of Research and Extension in Nutritional Genomics and Metabolic Dysfunctions (GENUT), Life Sciences Department (DCV), University of the State of Bahia (UNEB), Salvador, Brazil
| | - Najara Brandão
- Nucleus of Research and Extension in Nutritional Genomics and Metabolic Dysfunctions (GENUT), Life Sciences Department (DCV), University of the State of Bahia (UNEB), Salvador, Brazil
| | - Daniela Almeida
- Nucleus of Research and Extension in Nutritional Genomics and Metabolic Dysfunctions (GENUT), Life Sciences Department (DCV), University of the State of Bahia (UNEB), Salvador, Brazil.,Interactive Process of Organs and Systems (PPGorgsystem), Health Sciences Institute, Federal University of Bahia, Salvador, Brazil
| | - Gildásio Conceição
- Association of Parents and Friends of the Exceptional (APAE), Biochemical Analysis Laboratory, Salvador, Brazil
| | - Camila Figueredo
- Department of Biointeractive Science, Federal University of Bahia, Salvador, Brazil
| | - Hellen Fonseca
- Department of Biointeractive Science, Federal University of Bahia, Salvador, Brazil
| | - Maria de Lourdes Lima
- Bahia School of Medicine and Public Health (EBMSP), University Salvador (UNIFACS), Salvador, Brazil
| | - Denise Lemaire
- Nucleus of Research and Extension in Nutritional Genomics and Metabolic Dysfunctions (GENUT), Life Sciences Department (DCV), University of the State of Bahia (UNEB), Salvador, Brazil.,Interactive Process of Organs and Systems (PPGorgsystem), Health Sciences Institute, Federal University of Bahia, Salvador, Brazil
| | - Domingos Rios
- Nucleus of Research and Extension in Nutritional Genomics and Metabolic Dysfunctions (GENUT), Life Sciences Department (DCV), University of the State of Bahia (UNEB), Salvador, Brazil.,Posgraduate Program in Biotechnology (PPGBiotec), State University of Feira de Santana (UEFS), Salvador, Brazil
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6
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Comparison of Lactase Variant MCM6 -13910 C>T Testing and Self-report of Dairy Sensitivity in Patients With Irritable Bowel Syndrome. J Clin Gastroenterol 2019; 53:e227-e231. [PMID: 29912753 PMCID: PMC6295355 DOI: 10.1097/mcg.0000000000001065] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
GOALS To evaluate agreement of MCM6-13910 with self-report of dairy sensitivity (DS) and lactose hydrogen methane breath test (LHMBT) results in subjects with irritable bowel syndrome (IBS). BACKGROUND IBS is a functional gastrointestinal disorder with symptoms including abdominal pain, variable bowel habits, and bloating. Adult patients with lactose malabsorption may present with similar symptoms. Patients with lactose malabsorption have a lactase nonpersistent (LNP) phenotype. Recent studies found 2 single nucleotide polymorphisms associated with LNP: G/A-22018 and C/T-13910. STUDY Genotyping the MCM6-13910 variant of LNP in 538 IBS patients and 317 controls (without IBS). Subjects completed questionnaires pertaining to gastrointestinal problems and dietary consumption, with charts abstracted. RESULTS Self-reported DS was higher in IBS (45%) than controls (9.8%, odds ratio=6.46, P<0.001). The C/C-13910 genotype was similar in IBS cases and controls, 81 (15.1%) and 47 (14.8%). Among subjects reporting DS, 49 (18.0%) had the C/C genotype. Overall agreement between genotype and self-reported DS was 0.06 in IBS and 0.07 in controls. There were 20 subjects with LHMBT results; 3 had positive results, 17 were negative. LNP genotypes were found in all 3 of positive LHMBT results; 16 had negative LHMBT among the 17 who were lactase persistent. Agreement between C/C-13910 genotype and LHMBT was excellent with κ-statistic of 0.83 (0.50-1.00). CONCLUSIONS In IBS patients, self-report of lactose intolerance are highly prevalent but are a poor indicator of underlying C/C-13910 genotype. LHMBT had excellent agreement with C/C-13910 genotype.
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7
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Congruency of Genetic Predisposition to Lactase Persistence and Lactose Breath Test. Nutrients 2019; 11:nu11061383. [PMID: 31226742 PMCID: PMC6628305 DOI: 10.3390/nu11061383] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Revised: 06/13/2019] [Accepted: 06/18/2019] [Indexed: 12/16/2022] Open
Abstract
The physiological decline of lactase production in adulthood, in some individuals, is responsible for the so-called “Lactose Intolerance.” This clinical syndrome presents with gastrointestinal and non-gastrointestinal symptoms following the consumption of dairy containing food. Lactose intolerance can be evaluated by means of the Lactose Breath Test (phenotype) and/or genetic evaluation of lactase-gene polymorphism (genotype). A comparison of the two tests was carried out in a large number of symptomatic adult subjects, which are selected and not representative of the general population. Congruency was as high as 88.6%. Among lactase non-persistent (genotype C/C), 14 subjects showed a negative Lactose Breath Test (LBT), possibly due to young age. Among lactase-persistent (genotype C/T), four subjects showed a positive LBT, which helps to diagnose secondary lactose intolerance. Symptoms, both gastrointestinal and extra-gastrointestinal, were reported by 90% of patients during the breath test. Clinical use of both tests in the same patients could be taken into consideration as a sharp diagnostic tool. We suggest considering the use of the genetic test after LBT administration, when secondary hypolactasia is suspected, for completion of diagnostic procedures.
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8
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Tomczonek-Moruś J, Wojtasik A, Zeman K, Smolarz B, Bąk-Romaniszyn L. 13910C>T and 22018G>A LCT gene polymorphisms in diagnosing hypolactasia in children. United European Gastroenterol J 2018; 7:210-216. [PMID: 31080605 DOI: 10.1177/2050640618814136] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 10/28/2018] [Indexed: 11/17/2022] Open
Abstract
Background Primary lactose intolerance (PLI) is a gradual decrease of lactase activity that usually manifests at the age of 1-5 years. It has been proved that PLI is related to a single-nucleotide polymorphism of the lactase (LCT) gene. Objective An evaluation was performed on the usefulness of genetic tests in detecting LCT 13910C>T and 22018G>A polymorphisms in diagnosing lactose intolerance in children. Methods The study group included 99 children aged from 2 months to 16.5 years with different digestive tract symptoms. In all patients a hydrogen breath test (HBT) was conducted and blood samples were collected to determine LCT polymorphisms. PLI was defined as the presence of the 13910CC and/or 22018GG polymorphism in patients with a positive HBT result. Results In the group younger than 6 years, no statistically significant correlation was observed between the 13910CC and/or 22018GG LCT polymorphisms and HBT result. In the group of children older than 6, a statistically significant correlation between the 13910CC (p = 0.0011) and 22018GG (p = 0.003) LCT polymorphisms and HBT result was detected. Conclusions In children older than 6, the result of genetic testing based on LCT 13910C>T and 22018G>A polymorphisms may diagnose lactose intolerance.
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Affiliation(s)
- J Tomczonek-Moruś
- Department of Paediatrics, Immunology and Nephrology, Polish Mother's Memorial Hospital Research Institute, Łódź, Poland
| | - A Wojtasik
- Department of Paediatrics, Immunology and Nephrology, Polish Mother's Memorial Hospital Research Institute, Łódź, Poland
| | - K Zeman
- Department of Paediatrics, Immunology and Nephrology, Polish Mother's Memorial Hospital Research Institute, Łódź, Poland
| | - B Smolarz
- Department of Patomorphology, Polish Mother's Memorial Hospital Research Institute, Łódź, Poland
| | - L Bąk-Romaniszyn
- Department of Nutrition in Digestive Tract Disorders, Medical University, Łódź, Poland
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9
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Wortmann AC, Simon D, Mazzoleni LE, Sander GB, Francesconi CFDM, Nabinger DD, Grott CS, Rech TF, Mazzoleni F, Lunge VR, Bona LRD, Milbradt TC, Silveira TRD. The association between adult-type hypolactasia and symptoms of functional dyspepsia. Genet Mol Biol 2018; 41:92-97. [PMID: 29384557 PMCID: PMC5901505 DOI: 10.1590/1678-4685-gmb-2017-0015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 08/20/2017] [Indexed: 12/15/2022] Open
Abstract
Functional dyspepsia and lactose intolerance (adult-type hypolactasia, ATH) are
common conditions that may coexist or even be confounded. Their clinical
presentation can be similar, however, lactose intolerance does not form part of
the diagnostic investigation of functional dyspepsia. Studies on the association
between functional dyspepsia and ATH are scarce. This study aimed to evaluate
whether ATH is associated with symptoms of functional dyspepsia. Patients
fulfilling the Rome III diagnostic criteria for functional dyspepsia underwent
genetic testing for ATH. Dyspeptic symptoms were evaluated and scored according
to a validated questionnaire. The diagnostic criteria for ATH was a CC genotype
for the -13910C/T polymorphism, located upstream of the lactase gene. The mean
scores for dyspeptic symptoms were compared between patients with ATH and those
with lactase persistence. A total of 197 functional dyspeptic patients were
included in the study. Mean age was 47.7 years and 82.7% patients were women.
Eighty-eight patients (44.7%) had a diagnosis of ATH. Abdominal bloating scores
were higher in ATH patients compared to the lactase persistent patients
(P=0.014). The remaining dyspeptic symptom scores were not
significantly different between the two groups. The study results demonstrate an
association between ATH and bloating in patients with functional dyspepsia.
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Affiliation(s)
- André Castagna Wortmann
- Postgraduate Program in Sciences of Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
| | - Daniel Simon
- Human Molecular Genetics Laboratory, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil
| | - Luiz Edmundo Mazzoleni
- Postgraduate Program in Sciences of Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.,Division of Gastroenterology, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil
| | - Guilherme Becker Sander
- Division of Gastroenterology, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil
| | - Carlos Fernando de Magalhães Francesconi
- Postgraduate Program in Sciences of Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.,Division of Gastroenterology, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil
| | - Débora Dreher Nabinger
- Human Molecular Genetics Laboratory, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil
| | - Camila Schultz Grott
- Human Molecular Genetics Laboratory, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil
| | - Tássia Flores Rech
- Human Molecular Genetics Laboratory, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil
| | - Felipe Mazzoleni
- Division of Gastroenterology, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil
| | - Vagner Ricardo Lunge
- Molecular Diagnostic Laboratory, Universidade Luterana do Brasil (ULBRA), Canoas, RS, Brazil
| | - Laura Renata de Bona
- Division of Gastroenterology, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil
| | - Tobias Cancian Milbradt
- Division of Gastroenterology, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil
| | - Themis Reverbel da Silveira
- Postgraduate Program in Sciences of Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
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10
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Santonocito C, Scapaticci M, Guarino D, Annicchiarico EB, Lisci R, Penitente R, Gasbarrini A, Zuppi C, Capoluongo E. Lactose intolerance genetic testing: is it useful as routine screening? Results on 1426 south-central Italy patients. Clin Chim Acta 2014; 439:14-7. [PMID: 25281930 DOI: 10.1016/j.cca.2014.09.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Revised: 09/09/2014] [Accepted: 09/24/2014] [Indexed: 12/15/2022]
Abstract
Adult-type hypolactasia is a widespread condition throughout the world, causing lactose malabsorption. Several studies suggested that the identification of C/T-13910 and G/A-22018 mutations, located upstream the gene encoding the lactase-phlorizin hydrolase (LPH), is a useful tool for the differential diagnosis of hypolactasia. We evaluated the frequencies of C/T-13910 and G/A-22018 variants in a central-south Italian population and the usefulness of lactase deficiency genetic testing in the clinic practice. The genomic DNA of 1426 patients and 1000 healthy controls from central-south Italy was isolated from peripheral whole blood and genotyped for the C/T-13910 and G/A-22018 polymorphisms by high-resolution melting analysis (HRMA) and sequencing. The frequencies of genotypes in the 1426 patients analysed were as follows: 1077 CC/GG (75.5%), 287 CT/GA (20.1%), 24 TT/AA (1.7%), 38 CC/GA (2.7%). Only 64 out of 1426 (4.5%) performed also L-BHT test, 29 of which were negative for L-BHT also in presence of different genotypes. Among the 35 individuals with L-BHT positive, 34 were CC/GG and only one CT/GA. Although lactose genetic test is a good predictor of persistence/non-persistence lactase in specific population, its use in the central-south Italy population should be limited given the high prevalence of the CCGG diplotype in normal individuals.
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Affiliation(s)
- Concetta Santonocito
- Laboratory of Clinical Molecular and Personalized Diagnostics, Institute of Biochemistry and Clinical Biochemistry, Catholic University of the Sacred Heart, Rome, Italy.
| | - Margherita Scapaticci
- Laboratory of Clinical Molecular and Personalized Diagnostics, Institute of Biochemistry and Clinical Biochemistry, Catholic University of the Sacred Heart, Rome, Italy
| | - Donatella Guarino
- Laboratory of Clinical Molecular and Personalized Diagnostics, Institute of Biochemistry and Clinical Biochemistry, Catholic University of the Sacred Heart, Rome, Italy
| | | | - Rosalia Lisci
- Laboratory of Clinical Molecular and Personalized Diagnostics, Institute of Biochemistry and Clinical Biochemistry, Catholic University of the Sacred Heart, Rome, Italy
| | - Romina Penitente
- Laboratory of Clinical Molecular and Personalized Diagnostics, Institute of Biochemistry and Clinical Biochemistry, Catholic University of the Sacred Heart, Rome, Italy
| | - Antonio Gasbarrini
- Department of Internal Medicine, Teaching Hospital "A. Gemelli," Catholic University of the Sacred Heart, Rome, Italy
| | - Cecilia Zuppi
- Laboratory of Clinical Molecular and Personalized Diagnostics, Institute of Biochemistry and Clinical Biochemistry, Catholic University of the Sacred Heart, Rome, Italy
| | - Ettore Capoluongo
- Laboratory of Clinical Molecular and Personalized Diagnostics, Institute of Biochemistry and Clinical Biochemistry, Catholic University of the Sacred Heart, Rome, Italy.
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11
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Kumar S, Ranjan P, Mittal B, Singh R, Ghoshal UC. Lactase persistence/non-persistence genetic variants in irritable bowel syndrome in an endemic area for lactose malabsorption. J Gastroenterol Hepatol 2012; 27:1825-30. [PMID: 22989008 DOI: 10.1111/j.1440-1746.2012.07259.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/27/2012] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIM Lactase non-persistence is common in India. We evaluated: (i) frequency of lactase gene (C/T-13910 and G/A-22018) polymorphisms in irritable bowel syndrome (IBS) and healthy controls (HC), (ii) association between these polymorphisms and IBS-subtypes and symptoms. METHODS A total of 150 IBS patients (Rome-III criteria) and 252 age and gender-matched HC were evaluated for C/T-13910 and G/A-22018 genotypes using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS Totals of 79 (52%), 52 (35%) and 19 (13%) patients had diarrhea-predominant IBS (D-IBS), constipation predominant IBS (C-IBS) and alternating diarrhea and constipation IBS (A-IBS), respectively (Rome-III). Frequency of C/T-13910 [genotypes: CC 102 (68%), CT 43 (29%), TT 5 (3%) vs CC 155 (61%), CT 83 (33%), TT 14 (6%), P > 0.05] and G/A-22018 [GG 97 (65%), GA 41 (27%), AA 12 (8%) vs GG 154 (61%), GA 78 (31%), AA 20 (8%), P > 0.05] were similar among IBS and HC. Patients with D-IBS more often had C/T-13910 and G/A-22018 genotypes than C-IBS (CC 71 [90%], CT 6 [8%], TT 2 [2%]) versus (24 [46%], 25 [48%], 3 [6%]), A-IBS (7 [39%], 12 [63%], 0, [0%]) and HC (155 [61%], 83 [33%], 14 [6%]), P < 0.0001 and (GG 69 [87%], GA 6 [8%], AA 4 [5%]) vs (22 [42%], 24 [46%], 6 [12%]) vs (6 [32%], 11 [58%], 2 [10%]), P < 0.0001. IBS with CC and GG genotypes more often had abdominal pain (P = 0.005), distension (P = 0.031) and higher stool frequency (P = 0.003) and reported symptoms following dairy products than non-CC (P < 0.0001). CONCLUSION Though C/T-13910 and G/A-22018 polymorphisms were comparable among IBS and HC, these were more common among D-IBS and reported some symptoms like abdominal pain, bloating and exacerbation by dairy products.
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Affiliation(s)
- Sunil Kumar
- Department of Gastroenterology, Sanjay Gandhi Postgraduate Institute of Medical Science, Lucknow, Uttar Pradesh, India
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Wang WD, Fang XC, Ke MY. Role of food in onset of symptoms and treatment of irritable bowel syndrome. Shijie Huaren Xiaohua Zazhi 2012; 20:1531-1536. [DOI: 10.11569/wcjd.v20.i17.1531] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Epidemiological studies have suggested that the onset of some symptoms in patients with irritable bowel syndrome (IBS) is related with food. Although the potential mechanisms are not fully elucidated, there is some evidence that the inherent prokinetic and crinogenic effects of food components, food intolerance and allergies, as well as poor eating habits could plausibly contribute to symptom onset. Food elimination, supplemental dietary fiber, and special additives such as probiotics and prebiotics could relieve IBS symptoms. In this article we will review current advances in understanding the relationship between food and onset of IBS symptoms, the possible mechanisms, and emerging therapeutics involving dietary administration.
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Marton A, Xue X, Szilagyi A. Meta-analysis: the diagnostic accuracy of lactose breath hydrogen or lactose tolerance tests for predicting the North European lactase polymorphism C/T-13910. Aliment Pharmacol Ther 2012; 35:429-40. [PMID: 22211845 DOI: 10.1111/j.1365-2036.2011.04962.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND The diagnostic accuracy of two indirect tests of lactose digestion, lactose breath hydrogen and lactose tolerance tests, have not been systematically reviewed for comparison with available publications on genotype. AIM To perform a meta-analysis of available studies that compares the north-European genetic polymorphism C/T-13910 with the lactose breath hydrogen and the lactose tolerance tests, to determine their ability to predict geno/phenotype relationships. We examine the effects of lactose loading dose, inclusion of children and latitudes of study centre on comparative outcome. METHODS An electronic database of the literature as well as individual references in articles were searched with the theme of genetics of lactase and comparisons with breath or lactose tolerance tests were carried out. Random effect and fixed effect models were used for breath and lactose tolerance tests respectively, to report summary accuracy measures with 95% confidence intervals (CI). RESULTS The search revealed 19 studies: 17 evaluated breath hydrogen, five lactose tolerance test (3/17 overlapped). Overall sensitivity was 0.88 (CI, 0.85-0.90), specificity was 0.85 (CI, 0.82-0.87) for breath test. Heterogeneity was explored by adjusting for studies including children, high or low dose lactose and to some extent by site of study. The lactose tolerance test showed sensitivity of 0.94 (0.9-0.97) and specificity of 0.90 (0.84-0.95) with a nonsignificant heterogeneity. CONCLUSION The diagnostic accuracy of both tests individually reflects expected geno/phenotypes when the populations are well defined.
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Affiliation(s)
- A Marton
- Department of Medicine, MUHC, Montreal General Hospital, McGill University School of Medicine, Montreal, QC, Canada
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Haberkorn BCM, Ermens AAM, Koeken A, Cobbaert CM, van Guldener C. Improving diagnosis of adult-type hypolactasia in patients with abdominal complaints. Clin Chem Lab Med 2011; 50:119-23. [PMID: 21936609 DOI: 10.1515/cclm.2011.716] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 08/28/2011] [Indexed: 01/08/2023]
Abstract
BACKGROUND Adult-type hypolactasia is caused by genetic lactase non-persistence. It is the most common cause of lactose intolerance, which results in gastrointestinal symptoms after ingestion of dairy products. Currently, lactose intolerance is investigated by the hydrogen breath test (HBT), which is considered the preferred diagnostic test. Adult-type hypolactasia may also be diagnosed by genotyping. The single nucleotide polymorphism -13910C>T, which is located upstream of the lactase gene (LCT), is tightly associated with lactase persistence. Several other variants, mostly in non-European populations, can also lead to lactase persistence. This study investigated the accuracy of a modified, recently proposed algorithm which includes genotyping for the diagnosis of adult-type hypolactasia in a patient population with unexplained abdominal complaints. METHODS In 126 patients with unexplained abdominal symptoms or who were suspected to have adult-type hypolactasia, LCT genotyping by melting curve analysis on a LightCycler was performed. Those patients with CC(-13910) genotype (indicating loss of lactase expression) were directly referred to a dietician for a lactose-free diet. Those identified as CT(-13910) or TT(-13910) genotype underwent a HBT. Those who tested positive for hydrogen were also referred to a dietician for a lactose-free diet. The response to diet modification was recorded. RESULTS Genotype prevalences were: CC(-13910): 43 (34.1%); CT(-13910): 48 (38.1%); TT(-13910): 33 (26.2%); TG-13915: 2 (1.6%). Eleven of 48 (23%) patients with CT(-13910)-genotype and 1/33 (3%) patients with TT(-13910)-genotype had a positive hydrogen breath test. They all improved after a lactose-free diet. Four of 43 (9%) patients with CC(-13910)-genotype still had symptoms after a lactose-free diet. CONCLUSIONS The results show that lactase-genotype testing can be used as a first step to diagnose lactose intolerance in a patient population with unexplained abdominal complaints. It accurately identifies the group of patients sensitive to lactose, those who need further breath testing and those in whom adult-type hypolactasia can be excluded with high probability without performing a HBT. This algorithm would save hydrogen breath testing in more than 50% of the patients who present with unexplained abdominal symptoms.
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Jellema P, Schellevis FG, van der Windt DAWM, Kneepkens CMF, van der Horst HE. Lactose malabsorption and intolerance: a systematic review on the diagnostic value of gastrointestinal symptoms and self-reported milk intolerance. QJM 2010; 103:555-72. [PMID: 20522486 DOI: 10.1093/qjmed/hcq082] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND When lactose malabsorption gives rise to symptoms, the result is called 'lactose intolerance'. Although lactose intolerance is often bothersome for patients, once recognized it may be managed by simple dietary adjustments. However, diagnosing lactose intolerance is not straightforward, especially in primary care. AIM To summarize available evidence on the diagnostic performance of gastrointestinal symptoms and self-reported milk (lactose) intolerance in primary care, and the relationship between lactose malabsorption and intolerance. DATA SOURCES PubMed, EMBASE and reference screening. STUDY SELECTION Studies were selected if the design was a primary diagnostic study; the patients were adults consulting because of non-acute abdominal symptoms; the diagnostic test included gastrointestinal symptoms and/or self-reported milk intolerance. A total of 26 primary diagnostic studies were included in the review. DATA EXTRACTION Quality assessment and data extraction were performed by two reviewers independently. They adhered to the most recent guidelines for conducting a diagnostic review as described in the Cochrane Diagnostic Reviewers' Handbook. RESULTS The diagnostic performance of diarrhea, abdominal pain, bloating, flatulence and self-reported milk intolerance was highly variable. A non-Caucasian ethnic origin was associated with the presence of lactose malabsorption. Both lactose malabsorbers and lactose absorbers reported symptoms during the lactose hydrogen breath test. CONCLUSION Our review shows that high-quality studies on the diagnosis of lactose malabsorption and intolerance in primary care are urgently needed. An important prerequisite would be to clearly define the concept of lactose intolerance, as well as how it should be assessed.
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Affiliation(s)
- P Jellema
- Department of General Practice, EMGO Institute for Health and Care research, VU University Medical Centre and NIVEL (Netherlands Institute for Health Services Research), Van der Boechorststraat 7, 1081 BT Amsterdam, The Netherlands
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Xu L, Sun H, Zhang X, Wang J, Sun D, Chen F, Bai J, Fu S. The -22018A allele matches the lactase persistence phenotype in northern Chinese populations. Scand J Gastroenterol 2010; 45:168-74. [PMID: 19947896 DOI: 10.3109/00365520903414176] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE It has been reported that some single-nucleotide polymorphisms (-13910C/T, -22018G/A, -13907C/G, -13915T/G, and -14010G/C) within the lactase gene are associated with lactase persistence. In our previous study, we found that -13910C/T is not a good predictor of lactase persistence in Chinese populations. To obtain a better understanding of the mechanism of lactase persistence, we examined the frequencies in Northern China of the four other alleles that are associated with lactase persistence. MATERIAL AND METHODS We evaluated the allele frequencies of -22018G/A, -13907C/G, -13915T/G, and -14010G/C in six northern Chinese populations (Manchu, Mongol, Hezhen, Oroqen, Kazak, and northern Han) using the methods of polymerase chain reaction-restriction fragment length polymorphism and resequencing. RESULTS By genotyping 1092 chromosomes, we found that the frequency of the -22018A allele was highest in the Kazak population and extremely low in the northern Han population. Although there are little available data about the frequency of lactase persistence in northern Chinese populations, we compared the allele frequencies with the phenotype frequencies that have been published previously. We found that the frequency of the -22018A allele was basically consistent with the reported frequencies of lactase persistence in Northern China. With respect to the -13907C/G, -13915T/G, and -14010G/C polymorphisms, we found no individuals with the derived allele. CONCLUSIONS The frequency of the -22018A allele differed significantly among the six populations and the frequency reflected the frequency of lactase persistence. Taking into consideration the results of previous studies, we believe that the origins of lactase persistence-associated alleles are different in different pastoral populations.
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Affiliation(s)
- Lidan Xu
- Laboratory of Medical Genetics, Harbin Medical University, Harbin, China
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Mattar R, Monteiro MDS, Silva JMKD, Carrilho FJ. LCT-22018G>A single nucleotide polymorphism is a better predictor of adult-type hypolactasia/lactase persistence in Japanese-Brazilians than LCT-13910C>T. Clinics (Sao Paulo) 2010; 65:1399. [PMID: 21340236 PMCID: PMC3020358 DOI: 10.1590/s1807-59322010001200030] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Rejane Mattar
- Hospital das Clínicas, Faculdade de Medicina, USP, São Paulo, SP, Brazil.
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Polymorphism in the oxytocin promoter region in patients with lactase non-persistence is not related to symptoms. BMC Gastroenterol 2009; 9:90. [PMID: 19943975 PMCID: PMC2789731 DOI: 10.1186/1471-230x-9-90] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 11/30/2009] [Indexed: 12/27/2022] Open
Abstract
Background Oxytocin and the oxytocin receptor have been demonstrated in the gastrointestinal (GI) tract and have been shown to exert physiological effects on gut motility. The role for oxytocin in the pathophysiology of GI complaints is unknown. The aim of this study was to examine genetic variations or polymorphism of oxytocin (OXT) and its receptor (OXTR) genes in patients with GI complaints without visible organic abnormalities. Methods Genetic variants in the OXT promoter region, and in the OXTR gene in DNA samples from 131 rigorously evaluated patients with Irritable Bowel Syndrome (IBS), 408 homozygous subjects referred for lactase (LCT-13910 C>T, rs4988235) genotyping, and 299 asymptomatic blood donors were compared. One polymorphism related to the OXT gene (rs6133010 A>G) and 4 related to the OXTR gene (rs1465386 G>T, rs3806675 G>A, rs968389 A>G, rs1042778 G>T) were selected for genotyping using Applied Biosystems 7900 HT allele discrimination assays. Results There were no statistically significant differences in the genotype or allele frequencies in any of the SNPs when IBS patients were compared to healthy controls. Among subjects referred for lactase genotyping, the rs6133010 A>G OXT promoter A/G genotype tended to be more common in the 154 non-persistent (27.3%) subjects than in the 254 lactase persistant (18.1%) subjects and in the healthy controls (19.4%) (p = 0.08). When direct comparing, the A/G genotype was less common in the OXT promoter region in controls (p = 0.09) and in subjects with lactase persistence (p = 0.03) compared to subjects with lactase non-persistence. When healthy controls were viewed according to their own LCT-13910 genotypes, the C/C lactase non-persistent controls had a higher frequency for the OXT promoter A/G genotype than LCT-13910 T/T lactase persistent controls (41.2% vs 13.1%). No significant differences in frequencies of the investigated OXTR SNPs were noted in this study. Conclusion The results suggest that polymorphism in the promoter region of the OXT gene is most common in subjects with lactase non-persistence. This polymorphism may not be related to GI symptoms, as it is related to lactase non-persistence also in healthy controls.
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Prevalence of adult-type hypolactasia as diagnosed with genetic and lactose hydrogen breath tests in Hungarians. Eur J Clin Nutr 2009; 63:909-12. [DOI: 10.1038/ejcn.2008.74] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Lactose digestion and the evolutionary genetics of lactase persistence. Hum Genet 2008; 124:579-91. [PMID: 19034520 DOI: 10.1007/s00439-008-0593-6] [Citation(s) in RCA: 217] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Accepted: 11/06/2008] [Indexed: 12/11/2022]
Abstract
It has been known for some 40 years that lactase production persists into adult life in some people but not in others. However, the mechanism and evolutionary significance of this variation have proved more elusive, and continue to excite the interest of investigators from different disciplines. This genetically determined trait differs in frequency worldwide and is due to cis-acting polymorphism of regulation of lactase gene expression. A single nucleotide polymorphism located 13.9 kb upstream from the lactase gene (C-13910 > T) was proposed to be the cause, and the -13910*T allele, which is widespread in Europe was found to be located on a very extended haplotype of 500 kb or more. The long region of haplotype conservation reflects a recent origin, and this, together with high frequencies, is evidence of positive selection, but also means that -13910*T might be an associated marker, rather than being causal of lactase persistence itself. Doubt about function was increased when it was shown that the original SNP did not account for lactase persistence in most African populations. However, the recent discovery that there are several other SNPs associated with lactase persistence in close proximity (within 100 bp), and that they all reside in a piece of sequence that has enhancer function in vitro, does suggest that they may each be functional, and their occurrence on different haplotype backgrounds shows that several independent mutations led to lactase persistence. Here we provide access to a database of worldwide distributions of lactase persistence and of the C-13910*T allele, as well as reviewing lactase molecular and population genetics and the role of selection in determining present day distributions of the lactase persistence phenotype.
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Single nucleotide polymorphism C/T(-13910), located upstream of the lactase gene, associated with adult-type hypolactasia: validation for clinical practice. Clin Biochem 2008; 41:628-30. [PMID: 18237552 DOI: 10.1016/j.clinbiochem.2008.01.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 12/28/2007] [Accepted: 01/04/2008] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To validate C/T(-13910) polymorphism associated with primary hypolactasia for clinical practice. DESIGN AND METHODS Lactose breath test and PCR-RFLP for the C/T(-13910) polymorphism were performed. RESULTS Twenty-seven of 28 patients with genotype CC had positive breath tests; all twenty-two patients with genotypes CT or TT had negative breath tests. Agreement of tests was high (p<0.0001; Kappa Index 0.96). CONCLUSION C/T(-13910) polymorphism detection may be a new tool for primary hypolactasia diagnosis.
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