Djurforskning: Utforma forskning inom hälsa och biomedicin

The Challenge

Most basic research with animal models focuses on males and excludes females (Zucker et al., 2010; Marts et al., 2004). This creates three problems:

  • Less knowledge about disease processes in females due to underutilization of female animals. Results of studies in males are often generalized to females without justification, and even some conditions that occur more often in women are studied in mostly male animals. A gap exists between the proportion of women in patient populations and the proportion of female animals used in testing.
  • Inability to use sex as a variable in studies of basic biology (Holdcroft, 2007). In many cases, sex has proven an important variable—for example, in regulation of immune function.
  • Missed opportunities to examine female-specific phenomena (such as pregnancy and, in some species, menopause) that often interact with disease progression. Studying pregnancy in model organisms is especially important given the safety concerns about testing in pregnant women.

Method: Designing Health & Biomedical Research

Countries typically have enacted legislation that requires inclusion of women in government-sponsored human studies. For example, the U.S. National Institutes of Health require “that women and members of minorities and their subpopulations” be included in all human subjects research (although sufficient representation of women to allow for sex analysis is required only for Phase III clinical trials—see Policy Timeline). These guidelines, however, rarely apply to studies conducted on animals even though sampling animals of both sexes and of various hormonal states has produced new discoveries that influence drug development and patient care.

Gendered Innovations:

  • Studying sex differences in animal models has led to new treatments for traumatic brain injury (TBI), is more common in men than women.
  • Accounting for pregnancy, estrous cycle, and menopausal status in animal models has revealed the biological influence of hormones on basic molecular pathways and has been important to understanding certain autoimmune diseases.
  • Regulators have considered sex in order to improve animal models for toxicity; this has led to stronger environmental health standards.