Replacing SATA M.2 with PCIe M.2

[mahesh]

I bought a System76 Gazelle laptop in March 2016 with an Intel Skylake Core i7 processor. The laptop came with a Samsung Evo SATA M.2 drive. Is it possible to swap out the SATA drive with an M.2 PCIe drive or is the slot not compatible? Wasn't sure if the M.2 slot was a shared PCIe and SATA slot or just SATA only.