Context: Ghrelin plays a major role in GH physiology and energy metabolism. Polymorphisms of its receptor (GH secretagogue receptor (GHSR)) may influence childhood growth and weight regulation.
Objective: To correlate GHSR polymorphisms with auxological parameters throughout childhood in a healthy cohort.
Study design: Longitudinal retrospective population-based genetic association study.
Subjects and methods: GHSR genotypes were evaluated in 1362 children and compared with height/length, weight, and body mass index (BMI) data across an observation span of 10 years (0, 1, 3, 5, 8, and 10 years). Five different GHSR SNPs (rs2922126, rs2981464, rs482204, rs562416, and rs572169), minor allele frequency >0.1, were genotyped. Identification of potential genetic associations with height, weight, and BMI, using additive and dominant/recessive models, was optimized by comparing allele or genotype frequencies between the tallest and the shortest 27% of subjects for each auxological variable. Significance of association was evaluated by χ(2) test.
Results: The rs482204 TT genotype, vs TC/CC, was associated with greater stature across the entire observation period (P<0.05). Similarly, the rs562416 TT genotype, vs TG/GG, correlated positively with tall stature at 3, 8, and 10 years. Other SNPs and genotypes showed no association with height at any age. No association was found between any tested SNPs and weight or BMI.
Conclusions: Longitudinal investigation between birth and 10 years in a population-based cohort revealed a significant association of the rs482204 and rs562416 GHSR polymorphisms on height, whereas no association between GHSR polymorphisms and weight or BMI was ascertainable.