MGC1, a globular cluster with hundreds of thousands of tightly closed very long-lived stars, is located about 65,000 light-years away from the center of the neighbouring Andromeda galaxy (M31). This globular cluster is considered to be one of the most isolated globular cluster in the Local Group, which represents the group of galaxies including the Milky Way among others.
In a paper submitted to The Astrophysical Journal, researchers reported that there are no evidences of dark matter haloes in MGC1.
Charlie Conroy, Abraham Loeb, & David N. Spergel. Evidence against dark matter halos surrounding the globular clusters MGC1 and NGC 2419. The Astrophysical Journal.
A. D. Mackey, A. M. N. Ferguson, M. J. Irwin, N. F. Martin, A. P. Huxor, N. R. Tanvir, S. C. Chapman, R. A. Ibata, G. F. Lewis, A. W. McConnachie, (2009). Deep Gemini/GMOS imaging of an extremely isolated globular cluster in the Local Group. MNRAS.