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2D:4D finger length ratio in the Chuvashian population
L Kalichman1, D Zorina, V Batsevich
1Department of Physical Therapy, Recanati School for Community Health Professions, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer Sheva 84105, Israel. kleonid@bgu.ac.il
This study examined the index finger to ring finger (2D:4D) ratio in Chuvashians, finding significant sex differences in finger length ratios and high symmetry between hands. Age also correlated with finger length ratios, suggesting potential secular trends.
Area of Science:
- Anthropology
- Human Biology
- Biometrics
Background:
- The 2D:4D ratio, a marker of prenatal androgen exposure, varies between sexes and populations.
- Understanding digit ratio variations and symmetry is crucial for anthropometric and evolutionary studies.
Purpose of the Study:
- To investigate the 2D:4D ratio, its components (phalangeal and metacarpal), and hand symmetry in a Chuvashian population.
- To explore potential sex differences and age-related trends in these measurements.
Main Methods:
- Radiographic analysis of index and ring finger lengths (phalanges and metacarpals) in 803 males and 738 females.
- Visual classification of finger length types (Type 1, 2, 3) and measurement of digit ratios.
- Statistical analysis of 2D:4D ratios, symmetry, sex differences, and age correlations.
Main Results:
- Men exhibited smaller measured 2D:4D ratios (phalangeal, metacarpal, and combined) than women.
- High significant symmetry was observed between right and left hand 2D:4D ratios across all measurement types.
- Age showed significant correlations with visual classification of finger length types, indicating potential secular trends.
Conclusions:
- The study confirms significant sex dimorphism in 2D:4D ratios within the Chuvashian sample.
- High bilateral symmetry in 2D:4D ratios suggests robust developmental processes.
- Observed age-related changes warrant further investigation and replication in diverse populations to confirm secular trends.
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