The invention relates to a refrigerated display case with an illuminated support member or ā
mullionā that efficiently transfers heat generated by at least one 
light emitting diode (LED) to warm and maintain door seals. The invention further relates to a low-profile, elongated LED 
light fixture that is retrofitted to the display case 
mullion to provide efficient illumination. The LED 
light fixture includes an elongated frame having a central hub extending longitudinally along the frame. A pair of opposed arms extending upwardly at an angle from the central hub, wherein the terminus of each arm has a curvilinear configuration that defines a 
receiver. At least one leg extends rearward from the central hub. Two legs are spaced a distance apart to define an elongated central cavity that receives a 
fastener for securement of the fixture to the vertical support within the display case. A 
printed circuit board resides within a channel of the central hub and a plurality of LEDs are electrically and mechanically connected to the circuit board. A substantially planar lens cover resides within the 
receiver for securement to the frame.