If the cause of inherited scoliosis is unknown, why are researchers looking at the genes of people with it?

What you are likely referring to is called familial idiopathic scoliosis. The term refers to a curvature of the spine (scoliosis) that runs in families (familial) but is of unknown cause (idiopathic).

Since researchers can’t find what the cause of the disorder is, they have started looking into the genes, chromosomes, and DNA, to see if they can find any abnormalities that may be occurring on that level. At this point, the research is encouraging as some researchers have found some abnormalities on chromosome 17, which may lead to further findings.