Insulin sensitivity (IS) is a key determinant of metabolic health and may share genetic factors with obesity-related traits. Previous large-scale genetic studies have identified variants associated wi Show more
Insulin sensitivity (IS) is a key determinant of metabolic health and may share genetic factors with obesity-related traits. Previous large-scale genetic studies have identified variants associated with IS as well as obesity related traits like body mass index (BMI) and waist-to-hip ratio (WHR). Notably, many of these associations are shared across traits, indicating a potential genetic overlap. However, the genetic intersection between IS and obesity-related traits remains underexplored. To explore this gap, we investigated associations between six IS indices, including fasting and post-glucose load measures, and genetic variants linked to BMI and WHR to determine their influence on IS and related cardiometabolic traits. To achieve this, we calculated six IS indices using fasting and oral glucose tolerance test (OGTT) data from 5,007 non-diabetic individuals, grouping them into fasting, OGTT Show less
To determine the prevalence of Melanocortin-4 Receptor (MC4R) mutations in a cohort of children and adolescents with overweight or obesity and to determine whether treatment responses differed between Show more
To determine the prevalence of Melanocortin-4 Receptor (MC4R) mutations in a cohort of children and adolescents with overweight or obesity and to determine whether treatment responses differed between carriers and noncarriers. Using target region capture sequencing, an MC4R mutation screen was performed in 1261 Danish children and adolescents enrolled at a tertiary multidisciplinary childhood obesity treatment center. Measurements of anthropometrics, blood pressure, fasting blood biochemistry including lipid and hormone levels, and dual-energy X-ray absorptiometry were performed at baseline and throughout treatment. Of 1209 children and adolescents that met all criteria to be included in the described analyses, 30 (2.5%) carried damaging or unresolved MC4R mutations. At baseline, mutation carriers exhibited higher concentrations of plasma thyroid-stimulating hormone (p = 0.003), and lower concentrations of plasma thyroxine (p = 0.010) compared to noncarriers. After a median of 1 year of treatment (range 0.5-4.0 years), body mass index (BMI) standard deviation score (SDS) was reduced in noncarriers but not in carriers, and this difference in treatment response was statistically significant (p = 0.005). Furthermore, HDL cholesterol was reduced in carriers, a response significantly different from that of noncarriers (p = 0.017). Among Danish children and adolescents with overweight or obesity entering a tertiary lifestyle intervention, 2.5% carried damaging or unresolved MC4R mutations. In contrast to noncarriers, carriers of damaging or unresolved MC4R mutations failed to reduce their BMI SDS during obesity treatment, indicating a need for personalized treatment based on the MC4R genotype. Show less