Analisis Interaksi Gen Epistatik pada Persilangan Drosophila melanogaster Strain W, Se, Y, dan Bar3

Abstract

Inheritance of traits in living organisms ideally follows Mendel’s laws; however, deviations frequently occur due to gene interactions. One important form of gene interaction is epistasis, in which one gene masks or modifies the expression of another non-allelic gene. This study aimed to analyze epistatic interactions and deviations from Mendelian inheritance in crosses of Drosophila melanogaster strains W, Se, Y, and Bar3 based on phenotypic observations of the F1 and F2 generations. A quantitative descriptive-experimental approach was employed through controlled and reciprocal crosses. Data were collected by observing phenotypes and sex of the offspring and analyzed using sex-chromosome and autosomal reconstruction as well as phenotypic ratio comparisons. The results showed that the F1 generation predominantly exhibited dominant phenotypes, whereas the F2 generation displayed phenotypic ratios deviating from classical Mendelian expectations, such as 9:3:4 and 12:3:1, indicating recessive and dominant epistasis. In addition, evidence of sex linkage affecting phenotypic distribution between males and females was observed. These findings demonstrate that epistasis plays a crucial role in phenotypic expression and confirm that Drosophila melanogaster is an effective model organism for studying gene interactions and deviations from Mendelian inheritance.

Keywords: epistasis; gene interaction; sex linkage; Drosophila melanogaster; inheritance