Leucine 7 to proline 7 polymorphism in the neuropeptide Y gene and changes in serum lipids during a family-based counselling intervention among school-aged children with a family history of CVD.

OBJECTIVE To compare whether serum lipids and their changes during a health education intervention are associated with the Leu7Pro polymorphism in the signal peptide part of neuropeptide Y (NPY) in children with normal weight and in those with overweight. DESIGN An intervention study. SETTING A family-based intervention of risk factors for prevention of CHD in Finland. SUBJECTS Subjects were 443 children with a family history of CVD participating in family-based health education. The children were divided into two groups according to NPY genotype: children with Leu7/Pro7 or Pro7/Pro7 genotype (n 50) and children with Leu7/Leu7 genotype (n 393). The final sample of the follow-up study included 353 (80 %) children (Pro7 allele carriers, n 43; Leu7/Leu7, n 310). RESULTS At baseline, the Leu7Pro polymorphism was not associated with serum lipid values after adjustment for body weight in boys or girls. There was a significant interaction of NPY genotype group by time and body weight (P = 0.043 for three-way interaction: time x NPY genotype x body weight) in LDL-cholesterol (LDL-C) concentration among boys. LDL-C decreased among boys with normal weight in both NPY groups and in overweight boys with the Leu7/Leu7 genotype, whereas it increased in overweight boys with the Pro7 allele. Two-way interaction (time x NPY genotype) showed no significant differences in changes of serum lipids between the NPY genotype groups among boys or girls. CONCLUSIONS The Leu7Pro polymorphism may be associated with dietary response to LDL-C concentration in overweight boys with a family history of early-onset CVD.