Association study of common functional genetic polymorphisms in SLC6A4 (5-HTT) and MAOA genes with obesity in portuguese children.

Objectives: To investigate the association of polymorphisms in SLC6A4 and MAOA genes with obesity indices in children.Material and Methods: A total of 637 Portuguese children (317 girls; 320 boys) aged 3-11 years-old were genotyped for the SLC6A4 polymorphisms, 5-HTTLPR and STin2, and for a MAOA VNTR. Polymorphisms were analysed by PCR-based methods.Results: Although non-significant (p = .089), our study revealed the Stin2 10 minor allele with a marked higher frequency in girls with overweight/obesity (0.466) in comparison with controls (0.376). Combining the two SLC6A4 polymorphisms, haplotype S/12 revealed in girls significant or nominally significant protective effects against BMI (β = -0.615; p = .009), BMI Z-score (β = -0.251; p = .006), WC (β = -1.4; p = .02) and WHtR (β = -0.008; p = .04).Conclusions: We found some evidences for the role of SLC6A4 gene in measures of childhood obesity, mainly in girls.