Objective: In this study, it was aimed to investigate the relationship of 2D:4D ratio with ABO and Rh blood groups.

Materials and Methods: A total of 1000 people, 500 women and 500 men, who did not have any chronic diseases and did not have any pathology or any history of surgical procedures on their hand were included in the study. The 2D and 4D lengths of their hands were measured and the 2D:4D ratio was calculated.

Results: It is found that in women; while the 2D:4D ratio is <0.98 in A Rh (+), O Rh (+), O Rh (-) and AB Rh (-) blood groups, this ratio is >0.98 in other blood groups, as it is common among women. In men; while the 2D:4D ratio was found to be >0.98 in individuals with AB Rh (-) blood group, the 2D:4D ratio was <0.98 in other blood groups, as it is common among men.

Conclusion: It is found that, the 2D:4D ratio of women with A Rh (+), O Rh (+), O Rh (-) and AB Rh (-) blood groups and men with AB Rh (-) blood groups is different from the 2D:4D ratio of most individuals in populations. The susceptibility of these individuals to diseases associated with the 2P:4P ratio can be revealed by large-scale studies, and in the light of the findings to be obtained, measures to protect these people against diseases can be taken from the time of birth.