Use of 3-d model for better understanding and long-term retention of molecular details of the dna structure

Introduction: 3-D structures and biochemical transformations at molecular level are difficult to simulate. The available DNA models are either highly complex to be routinely used for teaching or depict the salient features at the gross level only.

Objective:
1) To introduce 3 -D model for teaching DNA structure
2) To compare the use of 3-Dimensional Model and conventional PPT techniques for long term recall of the DNA structure at the atomic level

Methodology: DNA model was prepared from easily available materials like beads, wire etc., having the potential of being routinely used to study the complex 3-Dimensional DNA structure to a dimension at the atomic level. The DNA structure was taught to 141 1st MBBS students divided into 2 groups, using DNA model and PPT respectively. Pre-post and recall test after 3 months were conducted followed by crossover and feedback.

Results: 78% students found teaching using model better. Highly significant difference (p=0.000) was observed between Pre and Post test scores in the 2 groups. There was no significant difference between the 2 groups in the Pre test (p=0.592) and Post test scores (p=0.282) respectively. However significant difference (p=0.048) was observed in the Recall test scores with those taught using DNA Model performing better.

Conclusion: The use of different teaching aids did not affect the learning of the students on short term basis. As compared to PPT, DNA model having 3-D visualisation generated greater interest leading to better long term recall.