Should we be exploring a potential genetic link to autoimmune disease within my family?

My sisters have both been diagnosed with auto-immune disorders. My middle sister has severe psoriasis and psoriatic arthritis, my youngest sister was recently diagnosed with mixed connective tissue disease, which is apparently quite rare. She and my mother both have von Willebrand disease and Raynaud’s, which are shown to have some links to autoimmune diseases. I have two first cousins (on my mother’s side) with lupus, which (to the best of my knowledge) is believed to have genetic links.

No one else in my family (including myself) have ever been tested for autoimmune disorders. I rarely ever go to a doctor, so I personally have not had any kind of testing at all in quite a long time. Growing up, however, my doctors were always checking and monitoring my thyroid (hypothyroidism is also very prevalent in my family), because I have always had strong symptoms, but normal levels. All in all, we have always jokingly said that we are just victims of bad genes, since everyone in the family always seems to be ill in some way. It has become a running joke that one of us, or several of us, are constantly falling apart. It isn’t an issue of hypochondria, we just seem to be an unlucky bunch as far as health goes.

Is it possible that there is some underlying condition, or genetic predisposition to something specific that may be at the bottom of my own and my family’s chronic (and seemingly “rare”) illnesses? Perhaps being overlooked, since it has never come up before, and we all have seen different doctors up until recently? Now we are all going to the same physician, and it occurred to me that there may be some benefit in trying to see if it all ties together to some common, genetic link? Or is it just far more likely that this is a fluke? Should I look into testing for autoimmune disease for myself, am I at higher risk, or is this something that I shouldn’t concern myself with?