IRS1 and Infertility: Also, fertile and infertile persons atBMI >25 had 1.78 times (P=0.042, 95% CI: 0.214-2.026)more expression of the INSR gene and 2.19 times (P<0.0001,95% CI: 0.069-0.812) more expression of the IRS-1 gene.