ASSESSMENT OF SEXUAL DIMORPHISM OF FINGER LENGTH RATIO (2D:4D)

Maciej Mularczyk, Angelika Ziętek-Czeszak, Zbigniew Ziętek

Abstract


Introduction: Studies on many populations have shown that the length of the second finger (2D) compared to the fourth (4D), expressed as the finger length ratio (2D:4D), might be characteristic for sexual dimorphism. It was also found that the values of 2D:4D differ significantly between examined populations. It is thought that the value of 2D:4D is determined in early foetal life under the influence of genetic factors and the strong influence of sex hormones. It has been proven that the values of 2D:4D are related to, for instance, sexual orientation, and artistic and sporting ability. Recently, increasing interest in the clinical significance of finger length ratio in the diagnosis of somatic and mental disorders has been observed. For example, it was found that values of 2D:4D in individuals suffering from congenital adrenal hyperplasia or autism were significantly lower compared to healthy subjects. The aim of the study was to determine sexual dimorphism in finger length ratio among representatives of the Polish population.

Materials and methods: The study group comprised 115 people (57 females and 58 males). Anthropometric measurements were taken from the second and fourth finger of the right and left hands – from the point of dactylion (da) to pseudophalangion (pph) using analogue callipers. We calculated the significance of differences in 2D:4D between males and females separately for the right and left hands.

Results: In both hands mean 2D:4D values were lower in males than in females. The difference in the right hand reached the statistical significance level with p < 0.05.

Conclusions: Among the subjects from the examined population the 2D:4D ratio shows trends characteristic for sexual dimorphism.


Keywords


finger length ratio (2D:4D); sexual dimorphism; sex hormones

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DOI: https://doi.org/10.21164/pomjlifesci.10

Copyright (c) 2016 Maciej Mularczyk, Angelika Ziętek-Czeszak, Zbigniew Ziętek

License URL: https://creativecommons.org/licenses/by-nc-nd/3.0/pl/