Alcoholism and liver disease in Mexico: Genetic and environmental factors

Examining the effects of parental migration on youth mental health and substance use: a qualitative study in rural Yucatán, México

Background

Parental migration is common in Mexico and Latin America, where individuals pursue work to improve their family's economic opportunities and children remain home in their community under the care of the remaining parent or extended family. A research gap remains about the impact of parental migration on mental health and substance use in children who remain at home. The current study explored risk and resilience factors relating to mental health and substance use among Mexican youth remaining at home when one or more parents migrate.

Methods

This qualitative study applied attachment theory and thematic analysis to analyze 26 in-depth interviews with youth (17-21 years old), parents, and a focus group with high-school teachers in a town with history of migration both domestically and internationally (Yucatan, México).

Results

Respondents across groups perceived that parental migration was related to 1) less parental/caregiver oversight and support due to family demands on the remaining parent and 2) the deterioration of youth mental health. Lack of youth oversight and the poor mental health of youth were perceived as drivers of youth seeking out and consuming alcohol and substances. In terms of parental remittances, youth reported observing among their peers increased access to material goods such as clothing and technology (e.g., smartphones) and increased access to alcohol. Resilience factors included parental awareness of the role of good communication with youth and teachers and youth access to and utilization of self-care resources such as mutual aid meetings for substance use recovery.

Conclusion

Poor mental health and substance use among youth and parents were perceived to be related to parental absence, stressors on the remaining parent or family, and undermined healthy parent-child attachment. Youth themselves are a source of insight for recommendations on interventions to reduce youth isolation and substance use risk. We recommend the intentional engagement of youth in developing intervention research and tailoring evidence-based interventions to mitigate parental absence's impact and promote parent-child attachment for youth and families remaining at home.

Personalized medicine and nutrition in hepatology for preventing chronic liver disease in Mexico

Chronic liver disease is a global health issue. Patients with chronic liver disease require a fresh approach that focuses on the genetic and environmental factors that contribute to disease initiation and progression. Emerging knowledge in the fields of Genomic Medicine and Genomic Nutrition demonstrates differences between countries in terms of genetics and lifestyle risk factors such as diet, physical activity, and mental health in chronic liver disease, which serves as the foundation for the implementation of Personalized Medicine and Nutrition (PerMed-Nut) strategies. Most of the world's populations have descended from various ethnic groupings. Mexico's population has a tripartite ancestral background, consisting of Amerindian, European, and African lineages, which is common across Latin America's regional countries. The purpose of this review is to discuss the genetic and environmental components that could be incorporated into a PerMed-Nut model for metabolic-associated liver disease, viral hepatitis B and C, and hepatocellular carcinoma in Mexico. Additionally, the implementation of the PerMed-Nut approach will require updated medicine and nutrition education curricula. Training and equipping future health professionals and researchers with new clinical and investigative abilities focused on preventing liver illnesses in the field of genomic hepatology globally is a vision that clinicians and nutritionists should be concerned about.

The burden of liver disease in Latin America

Liver disease poses a substantial burden in Latin America. This burden is primarily attributed to a high level of alcohol consumption and the increasing prevalence of risk factors associated with metabolic dysfunction-associated steatotic liver disease (MASLD), such as sedentary lifestyles, easy access to ultra-processed foods, obesity, and type 2 diabetes mellitus. These epidemiological trends are cause for concern, especially considering that there are significant challenges in addressing them due to disparities in access to liver disease screening and care. In this article, we aim to provide an overview of the current situation regarding liver disease in Latin America. We also discuss recent multinational proposals designed to address the growing MASLD burden via its integration into existing non-communicable diseases policies, at both local and global levels. Additionally, we emphasize the urgent need to establish effective public health policies that target both MASLD risk factors and excessive alcohol consumption. Furthermore, we discuss the development of liver transplantation programs, areas for improvement in medical education and research capabilities, and how the fostering of extensive collaboration among all stakeholders is crucial for addressing liver disease in the region.

Binge drinking associated with mean temperature: a cross-sectional study among Mexican adults living in cities

BACKGROUND

The association between environmental temperature and alcohol consumption has not been widely explored despite the potential that increasing temperatures could promote the consumption of alcoholic beverages and the alcohol-related burden of disease. We aimed to explore the association between temperature and binge drinking in Mexican adults from urban cities, overall, and by alcoholic beverage type.

METHODS

Data on 10,552 adults ≥ 18 years was obtained from the 2016 National Survey on Drug, Alcohol, and Tobacco Consumption. The mean annual temperature at the municipality was obtained from the Mexican National Weather Service using monthly temperatures from 2015 to 2016. We analyzed binge drinking for all alcoholic beverages in the last year and by type of alcohol as beer, liquor, wine, and coolers. Associations between mean temperature over the past year and binge drinking over the past year among current drinkers were estimated using multilevel Poisson models with robust standard errors adjusted for age, sex, education level, marital status, and household socioeconomic status, with a fixed effect by region.

RESULTS

We observed a non-significant increase in the prevalence of binge drinking for every difference of 1 °C between municipalities of the same region. By alcohol type, a 1 °C increase in mean annual temperature across municipalities of the same region increased the prevalence of beer binge drinking in the past year by 0.9% (PR = 1.009, 95%CI 1.005, 1.013) among beer consumers and the prevalence of coolers' binge drinking by 3.0% (PR = 1.030, 95%CI 1.003, 1.057) in coolers consumers. We observed non-significant results for liquor binge drinking (PR = 1.047, 95%CI 0.994, 1.102) and wine binge drinking (PR = 1.047, 95% 0.944, 1.161).

CONCLUSION

People living in municipalities with higher temperatures reported a higher beer binge drinking in Mexican cities. This could account for 196,000 cases of beer binge drinking in 2016. The context of each country needs to be considered when generalizing these findings, and they need to be further explored with longitudinal data as there might be implications for climate change. If our findings are confirmed given the forecasted rising temperatures, we could expect an increase in binge drinking and therefore, in the alcohol burden of disease.

Predictors of Stigma toward Alcohol Misuse in Mexico

Objective: This study explored factors associated with public stigma toward individuals misusing alcohol in Mexico. Methods: A randomized experimental vignette methodology was used to assess multiple domains of substance use-related stigma and their relationship to the gender of the vignette subject and the sociodemographic characteristics of respondents. Results: Although levels of stigma toward women who were misusing alcohol did not differ significantly from stigma toward men misusing alcohol, stigma levels and type of stigma reported varied with the sociodemographic characteristics of respondents. Education level, gender, self-stigma and openness to seeking mental health services were differentially associated with the three stigma domains. Conclusions: Accordingly, targeted community based stigma reduction efforts are needed to decrease stigma toward those misusing alcohol, and to support treatment initiation, ongoing treatment engagement and long term recovery efforts. Suggestions for future research on the relationship between substance use and stigma are offered.

Liver cancer in Hidalgo State, Mexico: analysis of the status, risk factors and regional public health policy requirements: a cross-sectional correlational study

BACKGROUND

In Latin America, liver cancer is one of the top causes of cancer mortality. It is the fifth most common cause of death among malignant tumors in Mexico and is the leading cause in Hidalgo State (43.8% of the population living in poverty).

OBJECTIVE

To conduct a correlational analysis on the main risk factors for liver cancer in Hidalgo State, Mexico, including municipal disaggregation and comparison with the national level.

DESIGN AND SETTING

Cross-sectional, correlational, descriptive and comparative epidemiological study using Mexican governmental databases covering 1990-2019.

METHODS

A comprehensive review of the databases of the General Directorate of Health Information (DGIS) was performed to analyze official death figures, hospital discharges and national and municipal population projections, using specific search criteria defined in the Global Burden of Disease classification, based on the risk factors for liver cancer.

RESULTS

Liver cancer rates showed an evident rise in Hidalgo (183%), moving from 21st place in Mexico in 1990 to 9th place in 2019. This increase was correlated with alcoholism. An increasing trend for liver cancer deaths, of 133.89%, is projected for 2030. Females and the population over 60 years of age are more affected. There are some critical regions with liver cancer death rates twice the national rate or more.

CONCLUSION

Targeted effective public health strategies should be structured by identifying, characterizing and regionalizing critical marginalized municipalities that are vulnerable to alcoholism and other risk factors for liver cancer. This approach may be helpful for other states in Mexico or similar countries.

Liver Diseases in Latin America: Current Status, Unmet Needs, and Opportunities for Improvement

Purpose of review

To assess the current challenges regarding liver diseases, including the burden of disease, access to care, screening, and treatment needs in Latin America.

Recent findings

Latin America is a region with a rich multicultural heritage and important socioeconomic differences. The burden of liver diseases is high and mainly determined by a high level of alcohol intake and the surge of risk factors associated with NAFLD (i.e., sedentary lifestyles, broader access to highly processed foods, obesity, and type 2 diabetes mellitus). Hepatotropic viruses also play a role in the development of chronic liver diseases, although their comparative frequency has been decreasing over the last decades. There are important disparities in access to screening and treatment for liver diseases in Latin America, which are reflected in low access to critical treatments such as direct-acting antiviral agents and drugs to treat hepatocellular carcinoma. Also, important barriers to liver transplantation are present in multiple countries, including a low deceased donors' rate and a lack of availability in several countries (especially in Central America). Our region also has disadvantages in research and education in liver diseases, which limits regional academic development and improvement in quality of care of liver diseases.

Summary

In order to tackle an increasing health burden due to liver diseases, Latin America urgently needs tailored interventions aiming to control the main risk factors for these disorders through the establishment of effective public health policies. Also, development of liver transplantation programs and improvement of medical education and research capabilities as well as extensive collaboration between all stakeholders are keys to address the liver disease agenda in the region.

Alcoholic Liver Disease

Content available: Author Interview and Audio Recording.

Influence of genetic and environmental risk factors in the development of hepatocellular carcinoma in Mexico

The latest studies on the epidemiology of diverse types of cancers have located in the scene the relevance of liver tumors, particularly hepatocellular carcinoma (HCC). HCC is a life-threatening malignancy triggered by chronic exposure to hepatitis B and C viruses, excessive alcohol intake, hepatic lipid droplet accumulation, and aflatoxins that lead to persistent liver damage. The occurrence of such etiological risk factors deeply marks the variability in the incidence of HCC worldwide reflected by geography, ethnicity, age, and lifestyle factors influenced by cultural aspects. New perspectives on the primary risk factors and their potential gene-environment interactions (GxE) have been well-addressed in some cancers; however, it continues to be a partially characterized issue in liver malignancies. In this review, the epidemiology of the risk factors for HCC are described enhancing the GxE interactions identified in Mexico, which could mark the risk of this liver malignancy among the population and the measures needed to revert them. Updated healthcare policies focusing on preventive care should be tailored based on the genetic and environmental risk factors, which may influence the effect of the etiological agents of HCC. Robust regional investigations related to epidemiological, clinical, and basic studies are warranted to understand this health problem complying with the rules of ethnic, genetic, environmental, and social diversity.

A hospital-based study of the prevalence of HBV, HCV, HIV, and liver disease among a low-income population in West Mexico

INTRODUCTION AND OBJECTIVES

Viral hepatitis is a global health problem with unequal distribution of disease burden in which low-income people are at higher risk for acquisition and underlying liver diseases. This study aimed to seek the prevalence of hepatitis B and C viruses, HIV, and liver damage among low-income patients attending a public tertiary care hospital in West Mexico.

METHODS

A retrospective/cross-sectional study at the Department of Genomic Medicine in Hepatology was conducted between March 1, 2016 to March 30, 2017. A total of 10,352 patients tested for anti-HCV, HBsAg, or anti-HIV (n=23,074) were included. Age, gender, and hospital service were registered. Liver fibrosis was assessed using APRI and FIB-4 scores.

RESULTS

Overall, 3.9% were anti-HCV+ (305/7848), 1.0% were HBsAg+ (80/7894), and 2.9% were anti-HIV+ (210/7332). A 43.8% (750/1959) of patients negative for all viruses had either abnormal AST, ALT, or GGT (≥40 UI/L). Also, significant liver fibrosis (APRI ≥ 0.7) was prevalent in 10.6% (191/1804). In patients who tested positive for viral infections, liver fibrosis was detected in 20.4% (11/54) of HBsAg+, 34.2% (53/155) in anti-HCV+ and 15.5% (16/103) in anti-HIV+. Anti-HCV+ was highest in Geriatrics (11.1%), HBsAg+ in HIV patients (3.0%) and anti-HIV+ in Emergency room attendees (33.3%).

CONCLUSION

High seroprevalence of HCV, HBV, and HIV infections was found among the studied population. Significant liver fibrosis was detected in negative and positive patients for viral infections. Medical services need to continuously test for viral infections, promote early detection of chronic liver damage and identify target patients for elimination strategies to decrease disease burden.

Dietary, Cultural and Pathogens-Related Selective Pressures Shaped Differential Adaptive Evolution Among Native Mexican Populations

Native American genetic ancestry has been remarkably implicated with increased risk of diverse health issues in several Mexican populations, especially in relation to the dramatic changes in environmental, dietary, and cultural settings they have recently undergone. In particular, the effects of these ecological transitions and Westernization of lifestyles have been investigated so far predominantly on Mestizo individuals. Nevertheless, indigenous groups, rather than admixed Mexicans, have plausibly retained the highest proportions of genetic components shaped by natural selection in response to the ancient milieu experienced by Mexican ancestors during their pre-Columbian evolutionary history. These formerly adaptive variants have the potential to represent the genetic determinants of some biological traits that are peculiar to Mexican people, as well as a reservoir of loci with possible biomedical relevance. To test such a hypothesis, we used genome-wide genotype data to infer the unique adaptive evolution of Native Mexican groups selected as reasonable descendants of the main pre-Columbian Mexican civilizations. A combination of haplotype-based and gene-network analyses enabled us to detect genomic signatures ascribable to polygenic adaptive traits plausibly evolved by the main genetic clusters of Mexican indigenous populations to cope with local environmental and/or cultural conditions. Some of these adaptations were found to play a role in modulating the susceptibility/resistance of these groups to certain pathological conditions, thus providing new evidence that diverse selective pressures have contributed to shape the current biological and disease-risk patterns of present-day Native and Mestizo Mexican populations.

Mortality in the Americas from 2013 to 2015 resulting from diseases, conditions and injuries which are 100% alcohol-attributable

AIMS

To describe mortality in the Americas from 2013 to 2015 inclusive resulting from diseases, conditions and injuries which are 100% attributable to alcohol consumption.

DESIGN AND SETTING

Mortality registry, population-based study. The data come from 30 of the 35 countries of the Americas for the triennium of 2013 to 2015.

PARTICIPANTS AND CASES

A total of 18 673 791 deaths coded by three-digit ICD-10 codes were analyzed.

MEASUREMENTS

Cause (underlying), and age-specific and age-adjusted mortality rates were calculated by sex and country.

FINDINGS

From 2013 to 2015 inclusive, among 30 of the 35 countries of the Americas, an average of 85 032 deaths per year were entirely attributable to alcohol. Men accounted for 83.1% of all 100% alcohol-attributable deaths, and death rates were higher for men than for women across all countries; however, the ratios of 100% alcohol-attributable deaths by sex varied by country. The majority of all 100% alcohol-attributable deaths occurred among those aged under 60 years (64.9%) and were due to liver disease (63.9%) followed by neuropsychiatric disorders (27.4%). Age-adjusted 100% alcohol-attributable mortality rates were highest in Nicaragua (23.2 per 100 000) and Guatemala (19.0 per 100 000), although the majority of all 100% alcohol-attributable deaths occurred in the United States 36.9%), Brazil (24.8%), and Mexico (18.4%).

CONCLUSIONS

From 2013 to 2015, more than 85 000 deaths in the Americas were 100% attributable to alcohol. Most of those occurred in people under 60 years and the highest mortality rates occurred in the United States, Brazil and Mexico.

Awareness, Knowledge, and Misperceptions Related to Nonalcoholic Fatty Liver Disease in a Community Sample of Mexican-Origin Women: A Mixed Methods Study

Introduction: Mexican-origin women suffer disproportionate rates of nonalcoholic fatty liver disease (NAFLD) and research on how to tailor NAFLD treatment interventions for this population is lacking. Objectives: The purpose of this study was to assess awareness, knowledge, perceptions, and information sources related to NAFLD in a community-based sample of Mexican-origin women. Methods: This study employed a convergent parallel mixed-methods approach and consisted of a brief questionnaire (n = 194) and interviews (n = 26) among Mexican-origin women recruited from community-based settings including health fairs, churches, and community events. Participants were eligible if they identified as Mexican-origin, had a BMI ≥ 25 kg/m², were 18-64 years of age, had the ability to speak, read, and write in English and/or Spanish, and provided informed consent. A purposeful sampling approach was used to recruit a subset of women (n = 26) with confirmed liver steatosis indicative of NAFLD (controlled attenuation parameter ≥280 dB/m) who completed the questionnaire. The twenty-six participants then completed one on one, in-depth semi-structured interviews to ascertain their knowledge and understanding of NAFLD. Results: Qualitative findings revealed low awareness of risk factors for liver disease, NAFLD specifically. Knowledge of liver disease tended to center around cirrhosis, a condition many participants reported was prevalent in their families. Quantitative and qualitative findings both found information sources for NAFLD and liver disease to be predominantly friends, family, and media. Interviews revealed a misperception related to NAFLD risk that liver disease was only caused by high alcohol intake. Conclusion: Low levels of NAFLD awareness and knowledge warrant the need for greater efforts to educate the general population, perhaps by integrating NAFLD education into existing type 2 diabetes educational campaigns and prevention interventions. Additionally, further elicitation research conducted in Mexican-origin adults is needed to elucidate key factors within behavioral-theory constructs that can be targeted in future interventions tailored to this unique population.

Tanshinone IIA exerts therapeutic effects by acting on endogenous stem cells in rats with liver cirrhosis

BACKGROUND AND OBJECTIVE

Liver cirrhosis (LC), the major pathway for the progression and development of chronic liver disease, is an advanced stage of liver disease. It is the third most common chronic noncommunicable disease after cardiovascular diseases and malignant tumors. Tanshinone IIA (Tan), an extract of Salvia miltiorrhiza (S. miltiorrhiza), has been proven to promote the proliferation and differentiation of stem cells. Moreover, its protective effect in liver injury has received widespread attention. The present study investigated whether Tan plays a therapeutic role in LC by promoting endogenous stem cell proliferation and differentiation.

MATERIALS AND METHODS

LC models were established by intraperitoneal injection of an olive oil solution containing 50 % carbon tetrachloride (CCL₄) combined with 10 % alcohol in the drinking water. After successful model establishment, the animals were randomly divided into four groups and injected with physiological saline or low-, medium-, or high-dose (10, 20, or 40 mg/kg) Tan for seven consecutive days. The protective effect of Tan on LC was observed by western blotting, serological examination and histopathological staining. Furthermore, immunofluorescence double-labeling of 5-bromo-2-deoxyuridine (BrdU) and the liver cell markers albumin and CK-18 or the liver stem cell markers EPCAM and OV-6 was used to evaluate the proliferation and differentiation of endogenous liver stem cells.

RESULTS

We confirmed successful establishment of the LC model by observing transaminase levels and hematoxylin-eosin (HE) and Masson staining of liver sections in CCL₄-treated and healthy rats. After Tan treatment, HE and Masson staining of paraffin sections of liver tissue showed that Tan treatment significantly improved histological injury to the liver. Serological tests showed that albumin-bilirubin (ALBI) scores and models for end-stage liver disease (MELD) were lower. Immunofluorescence and immunohistochemical staining showed that the newly proliferated cells were colocalized with ALB, OV-6, EPCAM, and CK-18, indicating that new expression of these markers occurred after Tan injection. All results were most significant in the medium-dose treatment group.

CONCLUSION

Tan can alleviate liver injury induced by CCL₄ combined with alcohol in rats and plays a therapeutic role in LC by promoting the proliferation and differentiation of endogenous liver stem cells.

Alcohol-related liver disease: Clinical practice guidelines by the Latin American Association for the Study of the Liver (ALEH)

Alcohol-related liver disease (ALD) is a major cause of advanced chronic liver disease in Latin-America, although data on prevalence is limited. Public health policies aimed at reducing the alarming prevalence of alcohol use disorder in Latin-America should be implemented. ALD comprises a clinical-pathological spectrum that ranges from steatosis, steatohepatitis to advanced forms such as alcoholic hepatitis (AH), cirrhosis and hepatocellular carcinoma. Besides genetic factors, the amount of alcohol consumption is the most important risk factor for the development of ALD. Continuous consumption of more than 3 standard drinks per day in men and more than 2 drinks per day in women increases the risk of developing liver disease. The pathogenesis of ALD is only partially understood and recent translational studies have identified novel therapeutic targets. Early forms of ALD are often missed and most clinical attention is focused on AH, which is defined as an abrupt onset of jaundice and liver-related complications. In patients with potential confounding factors, a transjugular biopsy is recommended. The standard therapy for AH (i.e. prednisolone) has not evolved in the last decades yet promising new therapies (i.e. G-CSF, N-acetylcysteine) have been recently proposed. In both patients with early and severe ALD, prolonged abstinence is the most efficient therapeutic measure to decrease long-term morbidity and mortality. A multidisciplinary team including alcohol addiction specialists is recommended to manage patients with ALD. Liver transplantation should be considered in the management of patients with end-stage ALD that do not recover despite abstinence. In selected cases, increasing number of centers are proposing early transplantation for patients with severe AH not responding to medical therapy.

Global hotspots and future prospects of chimeric antigen receptor T-cell therapy in cancer research: a bibliometric analysis

Aim: Our study aimed to analyze the characteristics of papers published on CAR T-cell in the field of cancer and explore the existing hot topics and prospects. Materials & methods: We explored the global hotspots and future prospects regarding CAR T-cell therapy in cancer research. Papers of CAR T-cell research were retrieved from the Web of Science database. Analysis was performed using VOSviewer, CiteSpace and Excel software. Results: A total number of 1994 papers related to CAR T-cell research of cancer were included. Molecular Therapy published the most papers (n = 85, 4.26%). A total of 9792 authors participated in the publication of all papers. 62 countries and 2065 institutions have participated in the publication of all papers. Conclusion: Research trends are to improve the immunosuppressive microenvironment of cancer, optimize the structure of CAR T-cells and develop ‘super CAR T-cell’ by using gene-editing technology.

RIESGO DE CÁNCER DE COLON EN DOCENTES UNIVERSITARIOS DE SALUD Y HUMANIDADES, UN ESTUDIO COMPARATIVO

<p><strong>Introducción:</strong> En México, el cáncer de colon ocupa el cuarto lugar de morbi-mortalidad con referencia a otros tipos de cáncer. Los factores de riesgo relacionados a la patología son: dieta hiperlipídica, sedentarismo, estrés, toxicomanías, enfermedades inflamatorias gastrointestinales; entre otros. La identificación de poblaciones expuestas, permite extender los alcances de la prevención primaria contra el cáncer de colon. La presente investigación, tuvo como O<strong>bjetivo:</strong> comparar el nivel de riesgo para desarrollar cáncer de colon en profesores de la Facultad de Estudios Superiores Iztacala (FES-I), con formación en ciencias de la salud y profesores de la Facultad de Estudios Superiores Acatlán (FES-A), dedicados a ciencias sociales y humanidades. <strong>Metodología:</strong> Se realizó un estudio cuantitativo, comparativo transversal, con muestra probabilística de 92 académicos de FES-A y 93 de FES-I. Se aplicó un instrumento de 40 ítems, fundamentado en los principales elementos que propician la aparición de cáncer de colon. <strong>Resultados: </strong>el análisis de datos, revela mayor porcentaje de obesidad, alto consumo de alcohol, tabaco y carnes rojas, así como menor conocimiento sobre factores predisponentes a la enfermedad, en docentes de FES-A. <strong>Conclusiones:</strong> los académicos de FES-A presentan más factores de riesgo que los profesores de FES-I. Es necesario difundir conocimiento de calidad sobre ésta patología para concientizar sobre hábitos inadecuados en la dieta, así como el consumo de alimentos protectores dentro de ella, para la prevención de esta neoplasia.</p>

Interactions between DRD2/ANKK1 TaqIA Polymorphism and Dietary Factors Influence Plasma Triglyceride Concentrations in Diabetic Patients from Western Mexico: A Cross-sectional Study

This study aimed to screen relevant interactions between DRD2/ANKK1 TaqIA polymorphism and dietary intakes with reference to phenotypical features in patients with T2D from western Mexico. In this cross-sectional study, a total of 175 T2D patients were enrolled. Dietary intake was evaluated using 3-day food records and appropriate software. Glycemic and blood lipid profiles were measured by standardized methods. Genotyping of the DRD2/ANKK1 TaqIA polymorphism was performed by the RFLP method. Gene-diet interactions regarding anthropometric and metabolic phenotypes were screened by adjusted multiple linear regression analyses. Genotype frequencies of the DRD2/ANKK1 TaqIA polymorphism were A1A1 (16.0%), A1A2 (52.6%), and A2A2 (31.4%). Statistically significant interactions between the DRD2/ANKK1 TaqIA genotypes and dietary factors in relation to blood triglyceride (TG) levels were found. Carriers of the A1 allele (A1A1 homozygotes plus A1A2 heterozygotes) were protected from TG increases by maltose intake (P int. = 0.023). Instead, A2A2 homozygotes were susceptible to TG rises through consumptions of total fat (P int. = 0.041), monounsaturated fatty acids (P int. = 0.001), and dietary cholesterol (P int. = 0.019). This study suggests that the interactions between DRD2/ANKK1 TaqIA polymorphism and dietary factors (sugar and fats) influence TG levels in diabetic patients.

Association of Ambient Air Pollution with Increased Liver Enzymes in Korean Adults

An association between exposure to air pollution and liver enzymes in certain areas or older people has been reported in the literature; however, it cannot be generalized to the general population. We investigated the association between air pollution, liver enzyme levels, and alcohol consumption using nationwide data of South Korean adults. Air pollutants included particulate matter with an aerodynamic diameter ≤10 µm (PM₁₀), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and carbon monoxide (CO). Liver enzymes included alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Exposure to air pollutants were significantly associated with elevation of log ALT and log AST, especially increases from 0.0073 IU/L (95% confidence interval (CI) = 0.0042, 0.0104) to 0.0251 IU/L (95% CI = 0.0132, 0.0371) per interquartile range (IQR) increase of each pollutant (all pollutants: p < 0.001). Association of the liver enzymes with PM₁₀ (β (95% CI) = 0.0285 IU/L (0.0201, 0.0368) for log ALT; β (95% CI) = 0.0139 IU/L (0.0079, 0.0198) for log AST) and CO (β (95% CI) = 0.0247 IU/L (0.0182, 0.0311) for log ALT; β (95% CI) = 0.0164 IU/L (0.0118, 0.0210) for log AST) were only significant among drinkers. Our findings suggest that chronic exposure to PM₁₀ and CO is a risk factor for liver enzymes increases among the general adult population who admitted to drinking alcohol.

High prevalence of nonalcoholic steatohepatitis and abnormal liver stiffness in a young and obese Mexican population

OBJECTIVE

To identify nonalcoholic steatohepatitis (NASH) and liver stiffness in Mexican subjects with different body mass index (BMI).

METHODS

A cross-sectional study was conducted in 505 adults. Risk for NASH was defined as the presence of one or more of the following biochemical and metabolic parameters (BMPs): fasting glucose ≥100 mg/dl, triglycerides (TG) ≥150 mg/dl, homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.5, aspartate aminotransferase (AST) >54 IU/L and alanine aminotransferase (ALT) >42 IU/L. Body mass index measurement and nutritional assessment were performed by standard procedures. Liver fibrosis stage was determined by liver stiffness measurement using transitional elastography (TE) or by liver biopsy (LB).

RESULTS

Risk for NASH was 57% (290/505). Most BMPs values incremented by BMI category. Among 171 at-risk patients, 106 subjects were evaluated by TE and 65 subjects by LB. Abnormal liver stiffness (≥6.0 kPa) was prevalent in 54% (57/106) of the cases, whereas by LB, 91% (59/65) of patients with obesity had NASH and liver fibrosis. Furthermore, liver fibrosis was prevalent in 46% (6/13) in normal weight individuals, whereas 4.6% (3/65) of patients with a BMI ≥ 35 kg/m2 showed no histopathological abnormalities. Overall, 67.8% (116/171) of the patients had abnormal liver stiffness or NASH. The normal weight patients with liver damage consumed relatively a higher fat-rich diet compared to the other groups whereas the remaining subgroups shared a similar dietary pattern.

CONCLUSION

Young patients with overweight and obesity showed a high prevalence of altered BMPs related to abnormal liver stiffness assessed by TE and NASH by LB. Early diagnostic strategies are required to detect the risk for NASH and avoid further liver damage in populations with a rising prevalence of obesity by defining the risk factors involved in the onset and progression of NASH.

Clinical features of alcoholic hepatitis in latinos and caucasians: A single center experience

AIM

To study differences of presentation, management, and prognosis of alcoholic hepatitis in Latinos compared to Caucasians.

METHODS

We retrospectively screened 876 charts of Caucasian and Latino patients who were evaluated at University of California Davis Medical Center between 1/1/2002-12/31/2014 with the diagnosis of alcoholic liver disease. We identified and collected data on 137 Caucasians and 64 Latinos who met criteria for alcoholic hepatitis, including chronic history of heavy alcohol use, at least one episode of jaundice with bilirubin ≥ 3.0 or coagulopathy, new onset of liver decompensation or acute liver decompensation in known cirrhosis within 12 wk of last drink.

RESULTS

The mean age at presentation of alcoholic hepatitis was not significantly different between Latinos and Caucasians. There was significant lower rate of overall substance abuse in Caucasians compared to Latinos and Latinos had a higher rate of methamphetamine abuse (12.5% vs 0.7%) compared to Caucasians. Latinos had a higher mean number of hospitalizations (5.3 ± 5.6 vs 2.7 ± 2.7, P = 0.001) and mean Emergency Department visits (9.5 ± 10.8 vs 4.5 ± 4.1, P = 0.017) for alcohol related issues and complications compared to Caucasians. There was significantly higher rate of complications of portal hypertension including gastrointestinal bleeding (79.7% vs 45.3%, P < 0.001), spontaneous bacterial peritonitis (26.6% vs 9.5%, P = 0.003), and encephalopathy (81.2% vs 55.5%, P = 0.001) in Latinos compared to Caucasians.

CONCLUSION

Latinos have significant higher rates of utilization of acute care services for manifestations alcoholic hepatitis and complications suggesting poor access to outpatient care.

High Prevalence of ITPA Alleles Associated with Ribavirin-Induced Hemolytic Anemia Among Mexican Population

BACKGROUND

The prevalence of two functional polymorphisms (rs1127354 and rs7270101) of the inosine triphosphatase (ITPA) gene associated with ribavirin-induced hemolytic anemia (RIHA) during antiviral therapy for hepatitis C virus (HCV) infection varies by ethnicity. In Mexico, the distribution of these polymorphisms among Native Amerindians (NA) and admixed population (Mestizos) is unknown. This study aimed to determine the prevalence of the ITPA polymorphisms among healthy NA and Mestizos, as well as in HCV patients from West Mexico.

MATERIAL AND METHODS

In a cross-sectional study, 600 unrelated subjects (322 Mestizos, 100 NA, and 178 treatment-naïve, HCV-infected Mestizos patients) were enrolled. A medical history was registered. ITPA genotype was determined by Real-Time PCR. Fst-values and genetic relatedness between study and reference populations were assessed.

RESULTS

The frequency of the risk genotypes rs1127354CC and rs7270101AA was higher among NA (98-100%) than in Mestizos (87-92.9%), (p &amp;lt; 0.05). The NA presented the highest prevalence of the rs1127354CC genotype reported worldwide. The Fst-values revealed a genetic relatedness among Mexican NA, South Americans and African populations (p &amp;gt; 0.05). The frequency of the predicted risk for RIHA was higher among NA (98%) than in Mestizos (80.5%) and HCV-infected patients (81.5%) (p &amp;lt; 0 .01). The CC/AA alleles were associated with lower values of total bilirubin, aspartate/alanine aminotransferases, and aspartate-to-platelet-ratio-index score among HCV-patients.

CONCLUSION

A high prevalence of the ITPA polymorphisms associated with RIHA was found in Mexican NA. These polymorphisms could be a useful tool for evaluating potential adverse effects and the risk or benefit of antiviral therapy in Mexicans and other admixed populations.

Early Detection of Liver Damage in Mexican Patients with Chronic Liver Disease

BACKGROUND AND OBJECTIVE

Liver cirrhosis is usually detected at the later stages of disease. This study is aimed to detect liver damage in patients with chronic liver disease using transitional elastography (TE) and to assess the biochemical parameters associated with liver damage.

METHODS

In 578 patients, chronic liver disease based on etiology was diagnosed by clinical and laboratory tests. Liver damage was evaluated with TE (FibroScan®), while its association with biochemical parameters was performed using the logistic regression tests.

RESULTS

Overall, the main etiologies of liver damage were hepatitis C virus (HCV) (37%), alcoholic liver disease (ALD) (33%) and non-alcoholic steatohepatitis (NASH) (26%). Patients were 40 to 50 years of age. ALD and hepatitis B prevailed in men, whereas HCV and NASH in women. The stages of fibrosis were F0 (n = 121, 21%), F1 (n = 122, 21%), F2 (n = 58, 10%), F3 (n = 46, 8%) and F4 (n = 87, 15%). In patients with liver cirrhosis, ALD (n = 96/217, 45%), HCV (n = 94/217, 43%) and NASH (n = 21/217, 10%) were the leading etiologies. Platelets count (OR=3.31, 95%CI 1.61-6.78), glucose (OR=3.07, 95%CI 1.50-6.26), gamma-glutamyl-transferase (OR=3.60, 95%CI 1.79-7.25), albumin (OR=3.89, 95%CI 1.61-9.36), and total bilirubin (OR=3.93, 95%CI 1.41-10.91) were associated to advanced stages of fibrosis (F3-F4) regardless of etiology. The concordance and positive predictive values of these parameters were higher as compared to other scores.

CONCLUSION

Asymptomatic liver disease due to HCV, ALD and NASH prevailed in young adults. Advanced liver damage assessed by TE was associated with five biochemical parameters. In conjunction, both methodologies may be useful for the early detection of fibrosis and cirrhosis in Latin America.

High frequency of the DRD2/ANKK1 A1 allele in Mexican Native Amerindians and Mestizos and its association with alcohol consumption

BACKGROUND

Mexico has an ancient tradition of alcohol drinking influenced by genetic and sociocultural factors. This study aimed to determine the distribution of the DRD2/ANKK1 TaqIA polymorphism in Mexican populations and to analyze its association with heavy drinking.

METHODS

In a cross-sectional and analytical study, 680 unrelated subjects including two Native Amerindians groups (87 Nahuas and 139 Huicholes), and two Mestizos groups (158 subjects from Tepic, Nayarit and 296 subjects from Guadalajara, Jalisco) were enrolled. DRD2/ANKK1 genotyping was performed by PCR-RFLP and allelic discrimination assays. Genetic analyses were conducted by Arlequin and Structure software. Heavy drinking was defined as ≥300g alcohol/week. The association of the DRD2/ANKK1 TaqIA polymorphism with heavy drinking was estimated.

RESULTS

Heavy drinking was prevalent in 64.7% of the study population. The DRD2/ANKK1 A1 allele prevailed in 67% and 65% of Nahuas and Huicholes, respectively and 51% and 47.3% in Mestizos from Tepic and Guadalajara, respectively. Heavy drinking was associated with the A1A1 genotype in the Mestizos of Guadalajara (A1A1 vs. A1A2 OR=4.79, 95%CI 1.81-12.68, p=0.0006; A1A1 vs. A1A2+A2A2, OR=4.09, 95%CI 1.56-10.68, p=0.0021) and in the Mestizos from Tepic (A1A1 vs. A1A2, OR=5.92, 95%CI 2.12-16.49, p=0.0002); A2A2, OR=14.56, 95%CI 3.57-59.24, p=0.00004); A1A2+A2A2, OR=6.68, 95%CI 2.42-18.42, p=0.00005). In Native Amerindians, a lack of association was found.

CONCLUSIONS

High frequencies of the DRD2/ANKK1 A1 allele were present in Mexican populations. Native Amerindians exhibited the highest frequencies of the A1 allele documented worldwide to date. The A1A1 genotype was associated with heavy drinking in Mestizos.

A pedigree-based proxy measure of genetic predisposition of drinking and alcohol use among female sex workers in China: a cross-sectional study

Scientific evidence has suggested that genetic factors accounted for more than half of the vulnerability of developing alcohol use problems. However, collecting genetic data poses a significant challenge for most population-based behavioral studies. The aim of this study was to assess the utilities of a pedigree-based proxy measure of genetic predisposition of drinking (GPD) and its effect on alcohol use behaviors as well as its interactions with personal and environmental factors. In the current study, cross-sectional data were collected from 700 female sex workers (FSW) in Guangxi, China. Participants provided information on a pedigree-based proxy measure of GPD and their alcohol use behaviors. Chi-square and independent t-test was applied for examining the bivariate associations between GPD and alcohol use behaviors; multivariate and ordinal regression models were used to examine the effect of GPD on alcohol use. This study found that women with a higher composite score of GPD tended to have a higher risk of alcohol use problem compared to their counterparts (p < .05). GPD was a significant predictor of alcohol use problems (p < .05), especially among women who had mental health issues or lack of health cares. The pedigree-based measure provided a useful proxy of GPD among participants. Both FSW's mental health and health care access interact with GPD and affect their drinking patterns. By understanding the genetic basis of alcohol use, we can develop scalable and efficacious interventions that will take into consideration the individual risk profile and environmental influences.

Development of an in vitro model to test antifibrotic drugs on primary human liver myofibroblasts

We have developed a culture model to assess antifibrotic drugs using normal human liver myofibroblasts (HLMFs) obtained from 31 subjects. Activation was evaluated in terms of α-smooth muscle actin (α-SMA) and collagen 1 (Coll1) expression using RT-PCR, and proliferation as the uptake of 5-ethynil-2'-deoxyuridine. Under analysis of variance, between-subject differences accounted for 70% of all variability and inter-experiment differences for 30%. The sensitivity of the model was determined by quantifying the effects in terms of relative expression, which were 0.74±0.03 for cyclosporine A (CsA) and 2.4±0.10 for transforming growth factor-beta (TGF-β) (P<0.0001 vs no treatment) for α-SMA expression. Inter-subject variations in α-SMA and Coll1 expression enabled the classification of subjects as potentially low or high fibrosers. Finally, we observed that pirfenidone (which has beneficial effects in vivo) significantly reduced the expressions of α-SMA and Coll1, whereas the angiotensin-converting enzyme inhibitor losartan (which has no effect in vivo) had no significant effect. Our model may thus detect the antifibrotic properties of drugs. Antifibrotic drugs with promising clinical relevance could possibly be selected using a bank of HLMFs from high fibrosers.

Biological mechanisms underlying evolutionary origins of psychotic and mood disorders

Psychotic and mood disorders are brain dysfunctions that are caused by gene environment interactions. Although these disorders are disadvantageous and involve behavioral phenotypes that decrease the reproductive success of afflicted individuals in the modern human society, the prevalence of these disorders have remained constant in the population. Here, we propose several biological mechanisms by which the genes associated with psychotic and mood disorders could be selected for in specific environmental conditions that provide evolutionary bases for explanations of when, why, and where these disorders emerged and have been maintained in humans. We discuss the evolutionary origins of psychotic and mood disorders with specific focuses on the roles of dopamine and serotonin in the conditions of social competitiveness/hierarchy and maternal care and other potential mechanisms, such as social network homophily and symbiosis.

Sweet Taste Receptor TAS1R2 Polymorphism (Val191Val) Is Associated with a Higher Carbohydrate Intake and Hypertriglyceridemia among the Population of West Mexico

Some high-carbohydrate diets may lead to obesity and multiple metabolic disorders, including hypertriglyceridemia (HTG). This lipid abnormality is considered an important risk factor for cardiovascular disease and type 2 diabetes. The sweet taste receptor TAS1R2 polymorphism (Ile191Val) has been reported to be associated with carbohydrate intake. The aim of this study was to analyze the association of the TAS1R2 gene polymorphism with carbohydrate intake and HTG among the population of West Mexico. In a cross-sectional study, 441 unrelated subjects were analyzed for TAS1R2 genotypes (Ile/Ile, Ile/Val and Val/Val) by an allelic discrimination assay. Biochemical tests and a three-day food record were assessed. The Val/Val genotype carriers had a higher intake of total carbohydrates, fiber and servings of cereals and vegetables than the other genotype carriers. The Val/Val genotype conferred a higher risk for HTG than the Ile/Val and Ile/Ile genotypes (OR = 3.26, 95%CI 1.35–7.86, p = 0.006 and OR = 2.61, 95%CI 1.12–6.07, p = 0.02, respectively). Furthermore, the Val/Val genotype was associated with approximately 30% higher triglycerides compared with Ile/Val and Ile/Ile genotypes (β = 44.09, 95%CI 9.94–78.25, p = 0.01 and β = 45.7, 95%CI 10.85–80.54, p = 0.01, respectively). In conclusion, the Val/Val genotype of TAS1R2 was associated with a higher carbohydrate intake and HTG.

Association with Spontaneous Hepatitis C Viral Clearance and Genetic Differentiation of IL28B/IFNL4 Haplotypes in Populations from Mexico

AIM

To analyze the genetic heterogeneity of the Amerindian and admixed population (Mestizos) based on the IL28B (rs12979860, rs8099917) and IFNL4 (rs368234815) haplotypes, and their association with spontaneous clearance (SC) and liver damage in patients with hepatitis C infection from West Mexico.

METHODS

A total of 711 subjects from West Mexico (181 Amerindians and 530 Mestizos) were studied for the prevalence of IL28B (rs12979860C/T, rs8099917G/T) and IFNL4 (rs368234815∆G/TT) genotypes. A case-control study was performed in 234 treatment-naïve HCV Mestizos (149 chronic hepatitis C and 85 with SC) for the association of haplotypes with SC and liver damage. A real-time PCR assay was used for genotyping, and transitional elastography staged liver damage.

RESULTS

Significant Fst-values indicated differentiation between the studied populations. The frequencies of the protective C, T, TT alleles were significantly lower in the Amerindians than in Mestizos (p<0.05). The r2 measure of linkage disequilibrium was significant for all variants and the T/G/ΔG risk haplotype predominated in Amerindians and secondly in Mestizos. The protective C/T/TT haplotype was associated with SC (OR = 0.46, 95% IC 0.22-0.95, p = 0.03) and less liver damage (OR = 0.32, 95% IC 0.10-0.97, p = 0.04) in chronic patients. The Structure software analysis demonstrated no significant differences in ancestry among SC and chronic patients.

CONCLUSIONS

West Mexico's population is genetically heterogeneous at the IL28B/IFNL4 polymorphisms. The T/G/ΔG high-risk haplotype predominated in Amerindians and the beneficial alternative haplotype in Mestizos. The C/T/TT haplotype was associated with SC and less liver damage in chronically infected Mestizo patients.

Changes of endogenous hydrogen sulfide in myocardial tissue of rats with cirrhotic cardiomyopathy

AIM: To observe the changes of endogenous hydrogen sulfide (H₂S) in myocardial tissue of rats with cirrhotic cardiomyopathy (CCM) of different severities, in order to investigate the role of H₂S in the pathogenesis of CCM.

METHODS: Forty SPF-grade male SD rats, weighing 220-250 g, were randomly divided into a blank control group (group N, n = 9) and a CCM model group (group M, n = 31). Group N was fed an ordinary diet and given tap water. Group M was subcutaneously injected with CCl₄ (3 mL/kg, given double dose for the first time) twice a week and given 100 mL/L ethanol in drinking water in the first two weeks, and 200 mL/L ethanol was given for the next two weeks. From the fifth week, rats with CCM started to drink 300 mL/L ethanol. At the end of the twelfth week, 9 rats (group M1) were randomly selected from group M and killed, while the rest (group M2) were killed at the fourteen week. Alanine aminotransferase (ALT), aspartate transaminase (AST), and total protein (TP) were detected. The concentration of H₂S in the myocardium was measured. Myocardial and liver pathology was assessed.

RESULTS: The levels of ALT and AST significantly increased and TP significantly decreased in the M1 and M2 groups compared with group N (P < 0.01). ALT and AST levels were also significantly higher in group M2 than in group M1. Compared with group N, the concentration of H₂S in groups M1 and M2 declined by up to 18% (P < 0.05) and 38% (P < 0.01), respectively, and the decrease was more significant in group M2 than in group M1 (P < 0.05). Group N had normal liver tissue, and groups M1 and M2 had hepatic cirrhosis, which was more severe in group M2. Group N had normal myocardial tissue. Myocardial cells were grossly normal but myocardial edema was seen in group M1. Myocardial edema and necrosis were observed in group M2.

CONCLUSION: In the process of liver cirrhosis, the protection on the myocardium becomes weak with the decreased level of endogenous hydrogen sulfide, which may play a crucial role in the pathogenesis of CCM.

Genetic, metabolic and environmental factors involved in the development of liver cirrhosis in Mexico

Liver cirrhosis (LC) is a chronic illness caused by inflammatory responses and progressive fibrosis. Globally, the most common causes of chronic liver disease include persistent alcohol abuse, followed by viral hepatitis infections and nonalcoholic fatty liver disease. However, regardless of the etiological factors, the susceptibility and degree of liver damage may be influenced by genetic polymorphisms that are associated with distinct ethnic and cultural backgrounds. Consequently, metabolic genes are influenced by variable environmental lifestyle factors, such as diet, physical inactivity, and emotional stress, which are associated with regional differences among populations. This Topic Highlight will focus on the genetic and environmental factors that may influence the metabolism of alcohol and nutrients in the setting of distinct etiologies of liver disease. The interaction between genes and environment in the current-day admixed population, Mestizo and Native Mexican, will be described. Additionally, genes involved in immune regulation, insulin sensitivity, oxidative stress and extracellular matrix deposition may modulate the degree of severity. In conclusion, LC is a complex disease. The onset, progression, and clinical outcome of LC among the Mexican population are influenced by specific genetic and environmental factors. Among these are an admixed genome with a heterogenic distribution of European, Amerindian and African ancestry; a high score of alcohol consumption; viral infections; a hepatopathogenic diet; and a high prevalence of obesity. The variance in risk factors among populations suggests that intervention strategies directed towards the prevention and management of LC should be tailored according to such population-based features.

Association of a novel TAS2R38 haplotype with alcohol intake among Mexican-Mestizo population

BACKGROUND

Alcohol intake has been associated with the bitter taste receptor T2R38. TAS2R38 gene expresses two common haplotypes: PAV and AVI. It has been reported that AVI homozygotes consume more alcohol than heterozygotes and PAV homozygotes. The aim of this study was to determine the prevalence of the TAS2R38 haplotypes among Mexican-Mestizo population and to analyze its association with alcohol intake.

MATERIAL AND METHODS

In a cross-sectional study, a total of 375 unrelated Mestizo individuals were genotyped for TAS2R38 polymorphisms (A49P, V262A and I296V) by a Real-Time PCR System (TaqMan). Haplotype frequencies were calculated. Association of TAS2R38 haplotypes with alcohol intake was estimated in drinkers (DRS) and nondrinkers (NDRS).

RESULTS

Two haplotypes accounted for over 96% of all haplotypes(AVV, 60%, and PAI, 36.5%). The frequency of AVV homozygotes was significantly higher in DRS than NDRS(47.2 vs. 32.2%, respectively; p < 0.05). Additionally, the AVV/AVV genotype was associated with alcohol intake when compared with heterozygotes and PAI homozygotes (OR = 1.79, 95% CI 1.13-2.84, p < 0.05 and OR = 2.23, 95% CI 1.11-4.48; p < 0.05, respectively).

CONCLUSIONS

In conclusion, two TAS2R38 haplotypes(AVV and PAI) prevailed in Mexican-Mestizo population. The novel AVV haplotype was associated with alcohol intake. The high prevalence of this allelic profile in our population could help to explain, at least in part, the preference for alcohol among the Mexicans.

Genomic medicine in gastroenterology: A new approach or a new specialty?

Throughout history, many medical milestones have been achieved to prevent and treat human diseases. Man's early conception of illness was naturally holistic or integrative. However, scientific knowledge was atomized into quantitative and qualitative research. In the field of medicine, the main trade-off was the creation of many medical specialties that commonly treat patients in advanced stages of disease. However, now that we are immersed in the post-genomic era, how should we reevaluate medicine? Genomic medicine has evoked a medical paradigm shift based on the plausibility to predict the genetic susceptibility to disease. Additionally, the development of chronic diseases should be viewed as a continuum of interactions between the individual's genetic make-up and environmental factors such as diet, physical activity, and emotions. Thus, personalized medicine is aimed at preventing or reversing clinical symptoms, and providing a better quality of life by integrating the genetic, environmental and cultural factors of diseases. Whether using genomic medicine in the field of gastroenterology is a new approach or a new medical specialty remains an open question. To address this issue, it will require the mutual work of educational and governmental authorities with public health professionals, with the goal of translating genomic medicine into better health policies.

Hepatitis B virus infection in Latin America: A genomic medicine approach

Hepatitis B virus (HBV) infection is the leading cause of severe chronic liver disease. This article provides a critical view of the importance of genomic medicine for the study of HBV infection and its clinical outcomes in Latin America. Three levels of evolutionary adaptation may correlate with the clinical outcomes of HBV infection. Infections in Latin America are predominantly of genotype H in Mexico and genotype F in Central and South America; these strains have historically circulated among the indigenous population. Both genotypes appear to be linked to a benign course of disease among the native and mestizo Mexicans and native South Americans. In contrast, genotypes F, A and D are common in acute and chronic infections among mestizos with Caucasian ancestry. Hepatocellular carcinoma is rare in Mexicans, but it has been associated with genotype F1b among Argentineans. This observation illustrates the significance of ascertaining the genetic and environmental factors involved in the development of HBV-related liver disease in Latin America, which contrast with those reported in other regions of the world.