The COBLL1 C allele is associated with lower serum insulin levels and lower insulin resistance in overweight and obese children

Background: Childhood obesity is a growing epidemic worldwide, and it is associated with metabolic complications, such as insulin resistance. Recently, a genetic variation (rs7607980) in the COBLL1 gene has been associated with lower insulin resistance in adults. The aim of the study was to investigate if the association between COBLL1 rs7607980 genetic variant and lower insulin resistance was present early in life. Methods: This sequence variant was genotyped in 878 overweight and obese children (mean age: 10 years) from Sardinia, Italy, from the outpatient clinic of the Pediatric Endocrine Unit, at the Regional Hospital for Microcitaemia in Cagliari. Insulin resistance was assessed by measurement of fasting circulating insulin levels before and after an oral glucose tolerance test and by HOMA-IR. Results: The COBLL1 rs7607980 C allele was associated with lower fasting insulin and HOMA-IR levels (p = 0.002 and p = 0.035, respectively) in overweight and obese children. Importantly, lower insulin levels were also observed 2 h after oral glucose tolerance test in C allele carriers (p = 0.009). Conclusions: The present study shows for the first time, the association between COBLL1 rs7607980 C allele, lower serum insulin levels and lower insulin resistance in overweight and obese children.