Final answer:
Genomic imprinting of genes like IGF2 affects the development of the reproductive system, with the SRY gene on the Y chromosome triggering the cascade for testes development and male differentiation in embryos.
Step-by-step explanation:
In genomic imprinting, genes such as IGF2 are differentially expressed depending on whether they are inherited from the male or the female parent. Such imprinting can significantly influence the development of various organs, most notably the gonads.
During the initial stages of embryonic development, a group of bipotential cells can develop into either male or female gonads. The presence of the SRY gene on the Y chromosome initiates a cascade of events that determine the development of these cells. In embryos with the SRY gene, which are genetically male (XY), this gene stimulates the development of testes, which in turn produce testosterone. This hormone is essential in further developing the male reproductive system. Conversely, in the absence of the SRY gene, as in female (XX) embryos, ovaries develop that produce estrogen, leading to the formation of the female reproductive system.
This process highlights the importance of specific genes in determining sexual differentiation during embryogenesis. Testosterone and estrogen are pivotal in this process, leading to the development of testes and ovaries, respectively.