Can one galaxy have a higher dark matter ratio than another? Dark matter do not interact with ordinary matter and light, it has mass and is affected by gravity. If the distribution of dark matter and ordinary matter is evenly spread at the early universe then I suppose the ratio should remain the same in every galaxy right? Or is there any mechanism for more dark matter to gather in some galaxies?
 A: Yes, absolutely. It's well known that the dark matter (DM) fraction varies from galaxy to galaxy, usually as a function of the galaxy (stellar or baryonic) mass. In general, the dark matter fraction is lowest for massive galaxies like our own Milky Way, and increases for both higher-mass galaxies (which are rare) and for lower-mass galaxies (which are common).
In addition, there have been recent claims that a few "ultra-diffuse" dwarf galaxies have very little dark matter, and that a few more gas-rich ultra-diffuse dwarfs may also mostly lack dark matter (see also here) So there is some evidence for large variations in the dark-matter fraction of dwarf galaxies, even though on average they tend to have higher dark-matter fractions than galaxies like the Milky Way.
There are generally two factors to consider: the first is how much dissipation the baryonic matter undergoes, which allows it to concentrate in the center of the galaxy (DM cannot undergo dissipation). The second is whether significant amounts of baryonic matter can be ejected from a galaxy due to star formation (strong stellar winds from massive stars, supernova explosions) and/or the action of an active galactic nucleus (e.g., jets from the accretion disk around a central supermassive black hole); these factors won't affect the DM except very indirectly (that is, if significant gas flows out of a galaxy, its gravity will pull somewhat on the DM).
Other possibilities include the effects of interactions, including tidal stripping of both dark matter and gas, ram-pressure stripping (which removes gas but not dark matter), etc.
A: Yes, some galaxies seem to have very little" dark matter". Also nobody knows for sure if dark matter is some exotic extraordinary matter(it isnt almost certainly) . It's just that most galaxies spin faster that their gravity alone can hold together. And some don't so they don't necessarily require an assumption of some strange matter. 
