1. Crime Scene Evidence: Investigators collected evidence from the crime scene, including DNA samples found at the scene.

2. DNA Extraction and Analysis: The collected DNA samples were carefully processed to extract DNA profiles. These profiles contain genetic information unique to each individual.

3. DNA Database Comparison: The extracted DNA profiles were then compared to existing DNA databases, such as those compiled from convicted offenders and arrestees.

4. Familial DNA Search: Since no direct match was initially found in the criminal databases, investigators employed a familial DNA search technique. This involves comparing the DNA profile of a close genetic relative of a suspect to the DNA evidence at the crime scene.

5. Identifying Close Relatives: Investigators were able to locate a close relative of the suspect, such as a parent or sibling, who had previously submitted their DNA to a database.

6. Matching Genetic Markers: By comparing the genetic markers of the suspect's close relative to the DNA profile found at the crime scene, investigators could narrow down the search for the suspect.

7. Additional Investigation: Further investigative efforts, such as surveillance, background checks, and witness accounts, were conducted to gather more evidence and corroborate the DNA findings.

8. Arrest and Identification: Based on the accumulated evidence, including DNA profiling, investigators identified and arrested the suspect, Bryan Kohberger, as the prime suspect in the Idaho student killings.