JACKIE JUDD:

The conclusion, according to Dr. Safer, is that gender identity cannot be manipulated or taught. A second set of data he reviewed involved the anatomy of the brain. Postmortem testing of women and males at birth who transitioned to females found certain regions to be strikingly similar, though Dr. Safer says more research is needed to determine if those regions are linked to gender identity.

At this lab at the University of Washington in Seattle, a unique long-term study is under way of transgender children, children as young as 3 years of age. With the support of their families, they have transitioned from the gender of their birth to what is called their expressed gender.

Skyler, along with several dozen other kids, both transgender and not, went through a battery of tests in the first phase of the study to pinpoint how they see themselves. This very quick picture and word association, called IAT, or Implicit Association Test, is intended to take a true measure of the strength of a child's identity.