The decimal issue you're showing here is very strange. I'm thinking:
- Why is
477_192314_7516-XRCC2_1from chr7 listed in the middle of these BRCA1 targets? The other targets here don't appear to be in genomic order, either. If the .cnn or .cnr files are scrambled, then that could lead to other issues. - It looks like the depth numbers 111095 and 87063 should be 111.095 and 87.063 if these are part of the same contiguous genomic region.
- The pattern there is that there are 3 trailing decimal places, which looks like a Euro-style thousands separator (vs. commas in the US locale), whereas 88.5551 has 4 decimal places and the decimal would not be mistaken for a thousands separator.
For the decimal issue, could you look at your system's locale settings and Python and pandas versions to see if your shell environment or pandas installation is mixing up . versus , thousands separators? My guess is that when the intermediate .cnn and .cnr files are being written by CNVkit via pandas, the decimal disappears because it looks like a thousands separator. But since the depth column isn't used for much after constructing the reference (check your reference.cnn file to see if the log2 values are wild there), it might not be the source of your main issue, the undetected BRCA1 deletion.
In your diagram or .cnr, do the log2 ratios look well-centered (mostly near 0), or is there a lot of noise and potentially off-center log2 ratios? If centering is the problem (maybe due to lots of outlier values), you could try re-centering with call -m median, or look further upstream to find the source of the outliers.
If it ultimately looks like a bug in CNVkit, could you try the latest from GitHub and/or tell me which version you're using?