The question of whether a baby inherits genes from a surrogate is common for those exploring surrogacy. Surrogacy involves various methods that impact the genetic relationship between the child and the individuals involved. Understanding the biological realities of genetic inheritance in surrogacy is a primary concern for many intended parents and surrogates. This article will clarify the genetic link, or lack thereof, between a baby and a surrogate depending on the type of surrogacy chosen.
Genes in Gestational Surrogacy
In gestational surrogacy, the surrogate carries a pregnancy that is not genetically related to her. The embryo is created outside her body using in vitro fertilization (IVF), fertilizing an egg with sperm in a laboratory setting. The egg and sperm can come from the intended parents, or from donor gametes.
Once the embryo develops, it is transferred to the gestational surrogate’s uterus. Her role is to provide the nurturing environment for the baby’s growth and development. The baby’s genetic material comes solely from the egg and sperm providers. This means that in gestational surrogacy, the baby will not inherit any physical characteristics or genetic traits from the surrogate.
Genes in Traditional Surrogacy
Traditional surrogacy involves a different genetic dynamic, as the surrogate is biologically and genetically related to the child. In this method, the surrogate uses her own egg, which is fertilized by sperm. This fertilization can occur through artificial insemination using the intended father’s sperm or donor sperm. Since the surrogate’s egg is used, she contributes half of the baby’s genetic makeup, making her the biological mother. This form of surrogacy is less common today due to the legal and emotional complexities that can arise from the genetic connection between the surrogate and the child.
Clarifying Genetic Misconceptions
A common misconception is that a surrogate’s DNA might transfer to the baby during pregnancy, or that the uterine environment alters the baby’s inherent genetic code. The placenta acts as a filter, allowing nutrients and oxygen to pass from the surrogate to the fetus while preventing the mixing of their blood and the transfer of genetic material.
The baby’s genetic blueprint is established at fertilization and remains unchanged throughout development. While the uterine environment is crucial for fetal development, influencing factors like nutrition and exposure, it does not modify the baby’s fundamental DNA sequence. The surrogate’s health and lifestyle during pregnancy can, however, influence gene expression through epigenetics. These epigenetic changes can affect how genes are turned “on” or “off,” potentially impacting aspects like metabolism or brain development, but they do not alter the baby’s genetic code itself.