Sex steroids: beyond conventional dimorphism.

Area of Science:

• Endocrinology
• Developmental Biology
• Evolutionary Biology

Background:

• Sexual dimorphism is observed across diverse species, from invertebrates to humans.
• Understanding the factors regulating sexual dimorphism, including determination, differentiation, and lifelong adaptation, remains a key scientific challenge.
• Sex steroids play a crucial role in sexual dimorphism, with ongoing research uncovering new production sites and actions.

Purpose of the Study:

• To review the fundamental principles of sex determination and sex steroid function.
• To present how modern research methods provide novel insights into the complexities of sexual dimorphism.
• To highlight the pervasive influence of sex steroids across bodily systems.

Main Methods:

• Literature review of classical principles in sex determination and steroid function.
• Integration of findings from modern biotechnology and high-tech research tools.
• Analysis of emerging data on novel steroid production sites and receptor actions.

Main Results:

• Sex steroids are central to establishing and maintaining sexual dimorphism.
• New research identifies additional sites of steroid production and action, including in the brain.
• Evidence suggests sex steroids affect virtually every part and system of the body.

Conclusions:

• The classical understanding of sex steroids requires a multifactorial re-evaluation.
• Modern research is revealing a more intricate and widespread role for sex steroids in sexual differentiation and function.
• Further investigation is needed to understand the full impact of sexual dimorphism on human evolution and health.