Heritability of serum leptin levels: a twin study / 中华医学遗传学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To study the contribution of genetic factors to the variance of serum leptin concentration in healthy, normotensive twins.</p><p><b>METHODS</b>A total of 57 pairs of twins were investigated 28 female and 19 male pairs of monozygotic(MZ) twins, and 6 female and 4 male pairs of dizygotic(DZ) twins. The zygosity of twins was determined by comparing the concordance of the genotype of nine fluorescence-labeled microsatellite markers. The genetic analysis was performed using the variance-based method. Serum leptin levels were determined in duplicate by a radioimmunoassay Kit (Linco Research, Inc., St. Charles, Missouri) as previously described.</p><p><b>RESULTS</b>The test of genetic variance revealed a significantly larger within-pair variance of serum leptin in the DZ twins, in comparison with the MZ twins. The corresponding heritability for serum leptin was 8%. Adjusted for BMI, gender, and uric acid (UA), the heritability for serum leptin was 0.18%. Log leptin correlated significantly with blood pressure (SBp r=0.355 P<0.001; DBp r=0.339 P<0.001). Stepwise multiple linear regression analysis revealed that only BMI, gender and UA were linked independently to serum leptin levels(R(2)=0.788, P<0.001).</p><p><b>CONCLUSION</b>The above data indicate that environmental factors other than genetic factors are important determinants of leptinemia in normal subjects.</p>