Evidence of sexual dimorphism in Fingerprint patterns of Children with Learning Disability

<b>Background</b>: Fingerprints are unique, permanent impressions on the finger, which is genetically determined at birth. Fingerprint pattern is an infallible means of personal bio identification and could be a predictive marker for several congenital disorders. The relationship between learning disability (LD) and fingerprint pattern is yet to be established. <b>Objectives</b>: This study compared the fingerprint patterns between students with LD and Non-LD students with a sexual dimorphic lens. <b>Materials and Methods</b>: 300 students (150 LD students and 150 non-LD students), aged between 3-25 years were recruited for this descriptive cross-sectional study. Each study group consisted of 75 males and 75 females. The different fingerprint patterns (arch, whorl, ulnar loop, and radial loop), as well as the following ridge counts: total finger ridge count (TFRC), absolute ridge count (ARC), ulnar ridge count (URC), and radial ridge count (RRC) were accessed using a digital scanner and a fingerprint reader. <b>Results</b>: Students with LD showed a higher frequency of whorl (32.87%), while non-LD students showed a higher occurrence of the ulnar loop (32.53%). TFRC, ARC, and URC were significantly higher in females with LD than non-LD females (<i>p</i>=0.01, 0.03, and 0.00, respectively). In contrast, males with LD showed significantly lower TFRC, RRC, and URC count than the non-LD males (<i>p=</i>0.02, 0.01, and 0.00, respectively). <b>Conclusion</b>: Fingerprints pattern and fingerprint ridge counts showed sexual dimorphism in LD and non-LD students. The finger ridge count is amplified in subjects with LD and could be a good predictive tool for LD.

**背景**：指纹是手指上独一无二且终身不变的印痕，其在出生时即由遗传决定。指纹模式是个人生物识别的可靠手段，同时可作为多种先天性疾病的预测标志物。目前学习障碍（Learning Disability，LD）与指纹模式之间的关联尚未明确。**研究目的**：本研究从性别二态性视角，对比了学习障碍学生与非学习障碍学生的指纹模式差异。**材料与方法**：本描述性横断面研究共招募300名学生，其中学习障碍学生与非学习障碍学生各150名，年龄介于3至25岁之间。两组研究对象均包含75名男性与75名女性。通过数字扫描仪与指纹阅读器，采集了包括弓型纹（arch）、斗型纹（whorl）、尺侧箕纹（ulnar loop）、桡侧箕纹（radial loop）在内的各类指纹模式，以及总指嵴数（Total Finger Ridge Count，TFRC）、绝对指嵴数（Absolute Ridge Count，ARC）、尺侧指嵴数（Ulnar Ridge Count，URC）与桡侧指嵴数（Radial Ridge Count，RRC）在内的多项指嵴计数指标。**结果**：学习障碍学生的斗型纹出现频率更高（32.87%），而非学习障碍学生的尺侧箕纹占比更高（32.53%）。学习障碍女性的总指嵴数、绝对指嵴数与尺侧指嵴数均显著高于非学习障碍女性（分别对应p=0.01、0.03与0.00）。与之相反，学习障碍男性的总指嵴数、桡侧指嵴数与尺侧指嵴数均显著低于非学习障碍男性（分别对应p=0.02、0.01与0.00）。**结论**：指纹模式与指嵴计数在学习障碍学生与非学习障碍学生中均表现出性别二态性。学习障碍受试者的指嵴数更高，可作为学习障碍的有效预测工具。