There are some grants for Research but these are institutional grants that go to the program and not the student, if those grants are divided up amongs med students working then you may get some piece of the pie, based on what I have seen and know, medical students are not given grant money, and it almost 100% of the time goes to funding the residency program, or funding an additional residency position.
Applying for personal grants for Dermatology Research is difficult, unless you are doing research in Skin Cancer, particularly melanoma, or aging, you won't be receiving any NIH grants.
There are 3 other research students who just started and will all take over when I leave derm research, and none of them are funded, 2 are from the school of origin, one is from Columbia, one student before me also was unfunded. More people are trying to get research where I am at not because its funded but because the PI is well known by all.
It is more than just to solidify your interests in academic medicine, you really have to make a lot of sacrifices if dermatology is what you are going for. Of course that is unless you got a 250+, your dad is a Mohs surgeon somehwere, or you cured atopic dermatitis
I would say go for the year of research, because it seems like it is becoming the standard of "how to get in". I dont know any medical student who had done a year of research before residency that wasnt given a ton of interviews.
Izzy