Scientific studies, like those from ResearchGate , have explored the ratio between the index (2D) and ring (4D) fingers as a biological marker, though results regarding gender identity are often mixed and not definitive for identifying individuals.

Qualitative Analysis of Thai Ladyboys' Occupational Wellbeing

Research highlighted by Academia.edu notes that stigma from family, community, and authority figures is common.

Transgender women may have physical characteristics from their male birth assignment, such as larger hands or distinct bone structures.