In individual SNP analyses , Gly482Ser ( rs8192678 , PPARGC1A ) was associated with accumulation of subcutaneous adiposity and worsening insulin resistance at 1 year ( both p < 0.05 ) , while rs2970852 ( PPARGC1A ) modified the effects of metformin on triacylglycerol levels ( p ( interaction ) = 0.04 ) .