Obesity is a significant health issue worldwide, progressing due to genetic factors and lifestyle. Melanocortin 4 receptor (MC4R) gene polymorphisms have been identified as a cause of overweight and o Show more
Obesity is a significant health issue worldwide, progressing due to genetic factors and lifestyle. Melanocortin 4 receptor (MC4R) gene polymorphisms have been identified as a cause of overweight and obesity risk. The aim of this study was a comprehensive assessment of MC4R polymorphism effects on overweight/obesity risk. All retrieved literature from PubMed, Web of Science and Scopus according to PRISMA guidelines up to June 2022 was reviewed. Inclusion criteria are restricted to English-language, human case-control/cohort studies with genotype distributions of MC4R polymorphisms and their association with obesity and overweight in any geographic regions and age. The heterogeneity using the I-squared statistic (I In our study, 39 eligible studies with 43 697 overweight and obese cases and 52 272 normal weights were included. In mixed-age populations, rs17700633, rs17782313, rs11872992, rs12970134, rs2229616 and rs571312 were evaluated. The remarkable association was seen by rs17782313 and rs12970134 in the Homozygous model (OR = 1.73; 95% CI: 1.51, 1.98 and 1.74; 95% CI: 1.29; 2.35, respectively). In addition, rs17782313 and rs12970134 were found to be more strongly linked to overweight and obesity in Asian and European population groups, as determined by a subgroup analysis of the geographic regions. The present study confirms the high association of rs17782313 and rs12970134 with obesity and overweight in all age groups and geographic regions. However, further functional studies and high-population research on other MC4R SNPs must validate their role. Show less
Depressed high-density lipoprotein cholesterol (HDL-C) is prevalent the Middle East and North Africa. Some studies have documented associations between HDL-C and several single nucleotide polymorphism Show more
Depressed high-density lipoprotein cholesterol (HDL-C) is prevalent the Middle East and North Africa. Some studies have documented associations between HDL-C and several single nucleotide polymorphisms (SNPs) in candidate gene polymorphisms. We investigated the associations between SNP genotypes and HDL-C levels in Iranian students, aged 10-18 years. Genotyping was performed in 750 randomly selected participants among those with low HDL-C levels (below 5th percentile), intermediate HDL-C levels (5-95th) and high HDL-C levels (above the 95th percentile). Minor allele frequencies (MAFs) of the SNPs of interest were compared between the three HDL-C groups. The vast majority of pairwise comparisons of MAFs between HDL-C groups were significant. Pairwise comparisons between low and high HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for APOC3 rs5128. Pairwise comparisons between low and intermediate HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for APOC3 rs5128 and APOA1 rs2893157. Pairwise comparisons between intermediate and high HDL-C groups showed significant between-group differences in MAFs for all SNPs, except for ABCA1 APOC3 rs5128 and APOA1 rs2893157. After adjustment for confounding factors, including age, sex, body mass index, low physical activity, consumption of saturated fats, and socioeconomic status, ABCA1 r1587K and CETP A373P significantly increased the risk of depressed HDL-C, and CETP Taq1 had a protective role. This study replicated several associations between HDL-C levels and candidate gene SNPs from genome-wide associations with HDL-C in Iranians from the pediatric age group. Show less