on the corresponding sizes (Sry: 402 bp, and Il3: 544 bp). Intensity of the corresponding bands was quantified using Adobe Photoshop CS5 software. The contribution of either sex was further determined by quantitative reverse transcription PCR (qRT-PCR) for Xist (X-inactive specific transcript) gene, as previously described, with minor modifications [39]. The PCR program for Xist included an initial denaturation at 95°C for 5 minutes; followed by 35 cycles of 95°C for 30 s, 53°C for 30 s, 72°C for 30 s, and 78°C for 30 s.
