Examples of undetected STRs for well-known genetic diseases. STRs within three genes including HTT, FRM1, and PABPN1 for two individuals (NA19238 and NA12878) could not be identified. The three bounding boxes represent the aligned results for three different genes. The unsuccessfully detected STRs in both HTT and PABPN1 genes were only for the NA19238 genome, and failed STR detection in FRM1 occurred for both NA12878 and NA19238 genomes. Flanking sequences of these STRs were well-aligned and are indicated using "*" symbols. It can be observed that the target STR was not detected due to absence of consensus STR segments (shown with the character "N"). Missing nucleotides might be caused by NGS sequencing issues or errors created during applying the SAM tool.