An analytical model of a dielectric-modulated double-gate Tunnel FET (DM-DG-TFET) biosensor carrying a Si(1-x) Ge(x) pocket is presented in this paper. The model accounts for the dielectric modulation effect on the surface potential and drain current of the designed biosensor device. An insight into the device physics provides an overview of commanding electrostatics and electrical properties associated with the proposed biosensor. The neutral, as well as charged nature of biomolecules, is considered for modeling and simulation data. Furthermore, the sensitivity for both types of biomolecules is analyzed in terms of threshold voltage (Vth) and on-current (Ion). The modeled and simulated results are extensively studied and compared for their scrupulosity. It has been found that the simulated and modeled results are a close match with each other, and the developed model justifies the physics behind the proposed biosensor. This paper also includes the impact of the nature of biomolecules on various parameters such as threshold voltage, sensitivity metrics, etc.