Genetic underpinnings of lung function and COPD

Spirometry based measurement of lung function is a global initiative for chronic obstructive lung disease (GOLD) standard to diagnose chronic obstructive pulmonary disease (COPD), one of the leading causes of mortality worldwide. Theenvironmental and behavioural risk factors for COPD includes tobacco smoking, air pollutants and biomass fuel exposure, which can induce one or more abnormal lung function patterns. While smoking remains the primary risk factor, only 15–20% smokers develop COPD, indicating that the genetic factors are also likely to play a role. According to the study of Global Burden of Disease 2015, ∼174 million people across the world have COPD. From a comprehensive literature search conducted using the ‘PubMed’ and ‘GWAS Catalogue’ databases, and reviewing the literature available, only a limited number of studies were identified which hadattempted to investigate the genetics of COPD and lung volumes, implying a huge research gap. With the advent of genomewide association studies several genetic variants linked to lung function and COPD, like HHIP, HTR4, ADAM19 and GSTCD etc., have been found and validated in different population groups, suggesting their potential role in determining lung volume and risk for COPD. This article aims at reviewing the present knowledge of the genetics of lung function and COPD

Genetics of nonalcoholic fatty liver disease in Asian populations

Nonalcoholic fatty liver disease (NAFLD) is characterized by the accumulation of fat in the liver without any history of chronic alcohol consumption. It encompasses a wide spectrum of diseases that range from simple steatosis to nonalcoholicsteatohepatitis. NAFLD is strongly associated with obesity, insulin resistance / type-2 diabetes mellitus and the metabolic syndrome. NAFLD is a complex disorder; environmental and genetic factors interact with NAFLD manifestation and determine its progression. In this review, an attempt was made to provide current information on the genetic variants of NAFLD in Asian populations. Literature search was performed by using PubMed, Medline and Google Scholar database. Candidate gene, validation and genomewide association studies (GWASs) were included in this review. A total of 41 studies fulfilled inclusion criteria of which 12 candidate gene studies exclusively focussed on the PNPLA3 gene and 17 other studies on other important candidate genes such as NCANCILP2, PPARG,AGTR1, FABP1, APOC3 etc. reported significant association with NAFLD. Eight validation studies identified associations of variants on PNPLA3, LYPLAL1, TM6SF2, ADIPOR2, STAT3, GCKR, SAMM50 etc. with NAFLD. Thus, so far, four GWASs have been conducted in Asian population that reported PNPLA3, SAMM50, PARVB and GATAD2A genes which were significantly associated with NAFLD. Findings indicate that PNPLA3, APOC3, PPARG, NCAN and GCKR genes emerge out to be the important biological markers associated with NAFLD.