Ok, this is the first question I've posed to the forum since joining.

I've recently connected with four autosomal tested relatives of the 3C/4C range that helps me connect with a suspected Cherokee Indian 3GGM of mine. Family lore and much evidence strongly suggests she was either half or full blood Cherokee Indian. GEDMatch has identified a nice 15cM overlap on Chromosome 23 on nine relatives that could only have come from her due to the nature of the descent.

I wanted to compare this overlapping segment in the Admixture analysis to see how it might show up in Chromosome painting or others. Does this common segment correlate with other American Indian segments?

However, when I went to perform the check, Chromosome 23 isn't available. What am I missing? I think I'm finally close to another data point to support or not the heritage. Options? Suggestions?