In the SOS reference study , subjects homozygous for the d3-GHR weighed 4kg more ( P = 0.011 ) , and had larger waist-to-hip ratio ( WHR , P = 0.036 ) , larger waist circumference ( P = 0.016 ) , and more fat-free mass estimated from total body potassium ( P = 0.026 ) than grouped fl/d3 and fl/fl subjects ( d3-recessive genetic model ) .