Introduction: The Pro12Ala variant of the Peroxisome Proliferator Activated Receptor Gamma (PPARγ) is one of the critical genetic factor predispose to positive energy balance leading to obesity. Objective: This study aimed to determine the association between Pro12Ala variant in the PPARγ gene with body mass index (BMI) status, physical activity and fat intake among Malay children. Methods: A total of 119 participants aged between 9-11 years old from primary schools in Kota Bharu, Kelantan were recruited. Anthropometric measurements were taken and activity counts of the participants were recorded using accelerometer (Actigraph GT3X+). A food diary was distributed to all participants to collect the data of their fat intake. Genotyping was performed using High Resolution Melting (HRM) analysis. Data obtained were analysed using SPSS version 19. Results: There was a significant association between Pro12Ala variant in the PPARγ gene with BMI status. The allelic frequency of wildtype (Ala/ala) and heterozygous (Pro/ala) among overweight group were 0.83 and 0.17 respectively and 0.92 and 0.08 in the normal weight group (p=0.03). There was a significant difference in BMI, waist circumference and hip circumference between heterozygous and wildtype groups. Conclusion: The study found that there was a significant role of Pro12Ala variant in the PPARγ gene in overweight Malay children.
Background: The low yield and quality of buccal-derived genomic DNA have reduced its applicability in various genetic research. The aim of this study was to assess the quantity, purity and genotyping efficiency of genomic DNA isolated from neonatal buccal swabs. Methods: Paired buccal swabs and whole blood samples were collected from 60 neonates with the mean age 5 days (SD=1.57). The genomic DNA quantity and purity were measured by using Infinite® 200 PRO NanoQuant reader and agarose gel electrophoresis. High-resolution melting (HRM) analysis was used to analyse the sequence variants present in uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1 c.211G>A) and nuclear receptor subfamily 1, group I, member 3 (NR1I3 IVS8+116T>G) genes. Results: Buccal swabs provided lower mean genomic DNA concentration (18.78 ± 8.39 ng/μl versus 40.02 ± 13.03 ng/μl), yield (2.63 ± 1.17 μgversus8.00 ± 2.61 μg). The purity of buccal samples however were inconsistent with 16 samples (26.7%) having A260/280 ratios below 1.8 which indicated protein contamination. Genomic DNA purity for all blood samples were within the ideal range with average absorbance ratios of 1.8−2.0. However, all buccal genomic DNA demonstrated 100% genotype call rates for all variants. A complete genotype concordance was also observed between paired genomic DNA samples. Conclusion: Despite related to a reduced quantity and purity, neonatal buccal genomic DNA could generate reliable HRM genotyping results. Therefore, buccal swab collection is a promising alternative to the invasive blood sampling to provide genomic DNA for genetic analysis involving paediatric population.