Self-fertilization in human: having a male embryo without a father

Area of Science:

• Human Genetics
• Reproductive Biology
• Developmental Biology

Background:

• Chimeras result from the fusion of two zygotes, leading to individuals with genetically distinct tissues.
• Sexually mixed chimeras (XX/XY) can develop both ovarian and testicular tissues.
• Previous cases of chimerism have shown individuals reared as females successfully fathering children.

Purpose of the Study:

• To present a theoretical scenario of a human chimera fathering a child without a partner.
• To explore the biological mechanisms enabling self-fertilization in a specific XX/XY chimera.
• To explain how such a chimera could produce a male offspring.

Main Methods:

• The study presents a theoretical model based on known biological principles of chimerism and reproduction.
• It analyzes the potential functional anatomy of an XX/XY chimera with asymmetric gonad development.
• The mechanism of gamete production, fertilization, and embryonic development is described.

Main Results:

• The described chimera possesses a left ovary and a right testis, with associated reproductive ducts.
• Both gonads are functional post-puberty, producing oocytes and spermatozoa.
• Spermatozoa can access the abdominal cavity and be picked up by the contralateral oviduct for fertilization.

Conclusions:

• A human XX/XY chimera can potentially achieve self-fertilization and produce offspring.
• The described anatomical and functional arrangement facilitates internal fertilization and the creation of a male embryo (XY).
• This scenario highlights the complex reproductive possibilities within human chimerism.