Obesity is a growing epidemic due to an accelerated phase of industrialization and urbanization with the overfed people now outnumbered the underfed. It is the major public health problem with a lot of research interest as it is associated with many complicated chronic disorders such as type-2 diabetes, cardiovascular diseases (CVD) and cancers. A global estimation of 2.8 million deaths per year is due to obesity and there are tremendous on-going efforts to identify hosts and environmental factors that infl uence the cause and pathogenesis of obesity. Concerted efforts from different research groups had successfully shown that obese subjects have altered composition of gut microbiota and transplantation of this microbiota infl uences body weight in the germ-free recipient mice. The advancement of technology had made possible the study of gut microbiota which was unculturable for better understanding of their impact to human health. Rapid deep sequencing of DNA at reasonable cost through various options of platforms followed by data analysis using robust bioinformatic tools are an important way of analysing the gut microbiome. Here we review the role of gut microbiota which modulates host’s metabolic functions and gene expression, facilitating the extraction and storage of energy from the ingested dietary substances and leading to body-weight gain. We will discuss on the different techniques used, focusing on the high-defi nition technologies for the determination of the composition, function and ecology of gut microbiota. This allows the appropriate selection of platform which becomes the key for success of subsequent research.
Obesity

Introduction: Prevalence of Hepatitis B virus (HBV) infection among the non-indigenous people in Malaysia has been well established and range between 3% and 5%. However, data from the indigenous (Orang Asli) people is still lacking. The Negrito population is the most remotely located Orang Asli tribe with limited access to health care facilities. This study was undertaken to determine the epidemiology and seroprevalence of HBV infection among the Negrito. Methods: Surveys were conducted in five Negrito settlements in Kelantan and Perak states in Malaysia. A total of 150 participants were recruited. Clinical history was taken and physical examination was performed. Five millilitres of whole blood were collected and tested for hepatitis B surface antigen (HBsAg) using electrochemiluminescence immunoassay. Results: Participants were mainly from the Bateq (49.3%) and Mendriq (29.4%) sub-tribes. Overall, 13 subjects (8.7 %); nine males and four females were HBsAg positive. Nine of the HBsAg positive subjects were ≥35 years old. All of them had history of home deliver without evidence of antenatal record. Six (46%) of the HBsAg positive subjects had tattoo and body piercing in the past. Conclusion: The prevalence of HBV infection rate amongst the Negrito tribe is almost three-fold compared to the national rates. The reason for this finding remains unclear. Tattooing, body piercing and vertical transmission could be the main possible routes of transmission of HBV among the Negrito population in Malaysia.