Homosexuality via canalized sexual development: a testing protocol for a new epigenetic model

Area of Science:

• Developmental biology
• Genetics
• Neurobiology

Background:

• Homosexuality (HS) has been under-appreciated as a natural phenomenon.
• Neurobiology is increasingly recognizing HS as a common occurrence in nature.
• Existing models do not fully explain the biological underpinnings of HS.

Purpose of the Study:

• To advance an epigenetic model for the development of homosexuality (HS).
• To propose that epigenetic marks influence sexual development based on embryonic karyotype (XX vs. XY).
• To investigate the potential role of inherited epigenetic marks in HS.

Main Methods:

• Synthesis and reinterpretation of published studies.
• Development of an epigenetic model based on embryonic stem cell marks.
• Formulation of predictions based on the proposed epigenetic model.

Main Results:

• The model posits that epigenetic marks canalize sexual development by modulating testosterone sensitivity.
• It predicts stochastic inheritance of these marks across generations.
• This inheritance may lead to mosaicism in sexual development, including homosexual phenotypes.

Conclusions:

• Epigenetic mechanisms offer a plausible framework for understanding the development of homosexuality.
• The model provides testable predictions regarding inherited epigenetic marks.
• Analysis of human stem cell epigenetic profiles can validate this model.