Comparison of 2D:4D Digit Ratios in Children with Specific Learning Disorders and Healthy Controls

Şermin Bilgen Ulgar; Mehtap Eroğlu; Neşe Yakşi

doi:10.31067/acusaglik.1751676

Comparison of 2D:4D Digit Ratios in Children with Specific Learning Disorders and Healthy Controls

Abstract

Purpose: Prenatal androgen exposure, particularly testosterone, may play a pivotal role in shaping brain development and is hypothesised to affect intelligence and learning skills.The second-to-fourth digit ratio (2D:4D) is widely recognized as a biomarker for prenatal exposure to the androgenic hormone testosterone. The present study seeks to examine 2D:4D ratios in children diagnosed with specific learning disorder (SLD) and to assess comparatively these values with those of typically developing peers. Methods: Participants in the study were 94 children diagnosed with SLD and 57 healthy controls. Sociodemographic data were collected, and 2D:4D ratios for each hand were determined and differences between groups were examined. Results: Children diagnosed with SLD exhibited notably reduced 2D:4D digit ratios in both hands relative to typically developing peers. In the SLD group, lower 2D:4D ratios were observed in both sexes, with the difference reaching statistical significance for females’ left hand measurements. Conclusion: This evidence suggests that elevated testosterone exposure during the prenatal period may be implicated in the pathogenesis of SLD. By employing the non-invasive 2D:4D ratio, this study contributes to the growing body of evidence on biological markers associated with neurodevelopmental disorders.

Keywords

References

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Details

Primary Language

English

Subjects

Psychiatry

Journal Section

Research Article

Authors

Şermin Bilgen Ulgar ^*
0000-0001-5237-220X
Türkiye

Mehtap Eroğlu
0000-0002-5879-9412
Türkiye

Neşe Yakşi
0000-0002-6175-2359
Türkiye

Publication Date

January 16, 2026

Submission Date

July 26, 2025

Acceptance Date

October 27, 2025

Published in Issue

Year 2026 Volume: 17 Number: January, February, March 2026

DOI

https://doi.org/10.31067/acusaglik.1751676

IZ

https://izlik.org/JA83BG87GT

Cite

RIS / Bibtex

EndNote

Bilgen Ulgar Ş, Eroğlu M, Yakşi N (January 1, 2026) Comparison of 2D:4D Digit Ratios in Children with Specific Learning Disorders and Healthy Controls. Acıbadem Üniversitesi Sağlık Bilimleri Dergisi 17 January, February, March 2026