1) Targeted re-sequencing is used to detect sequence differences between an individual and a reference genome in order to identify genetic variants associated with diseases. It can be done using microarrays or next-generation sequencing (NGS). 2) Microarrays have simpler workflows but struggle with insertions/deletions and repeats, while NGS can detect more variant types but has more complex data analysis. 3) Both methods require validation before clinical use, but NGS typically has higher data quality, reproducibility, and ability to detect pathogenic mutations while reducing incidental findings compared to microarrays.