Under the Microscope – Jennifer Cihlar

Massively parallel sequencing (MPS) technologies have been extensively evaluated by forensic genomic Research and Development laboratories for the past ten years. Results from these studies have routinely demonstrated the benefits afforded by use of these enhanced technologies and have helped progress the adoption of MPS in forensic genomic laboratories that process biological evidence. The commercial availability of MPS kits targeting forensic loci, developmental validation studies, and NDIS acceptance across multiple MPS kits and platforms illustrate the progress in reliability and adoption of MPS technologies in forensic laboratories. However, due to the financial investment necessary for acquiring a MPS instrument, forensic laboratories are likely to have only one MPS platform available in their laboratory once the decision to implement this technology is made. Since there are multiple platforms and chemistries, cross-platform workflows are needed to enable sharing of MPS data generated across the forensic genomics community.


In her presentation at ISHI 32, Jennifer Cihlar will share a study in which a set of samples (n=18) and dilution series with DNA input amounts ranging from 1ng to 62.5pg of DNA were amplified with the Promega PowerSeq 46GY System, generating PCR products for autosomal and Y-STR loci designed to be 140 to 300 base-pairs in size. These PCR products were used for two separate library preparation workflows to enable sequencing on both the Verogen MiSeq FGx System and the Ion Torrent Ion S5 System. Raw data generated by each workflow were then analyzed with three separate bioinformatic pipelines, which included STRait Razor, GeneMarkerHTS software, and Ion Torrent plugins available on the Ion Torrent Server.


We chatted with Jennifer to discuss the hurdles that still exist in adapting MPS/NGS technologies and why cross-platform workflows are needed within the community.



Although MPS/NGS has started to become adopted by forensic laboratories, there are many who have not yet brought on this technology? What hurdles still exist? Do you have advice for how to overcome them?

Validations and technology transfers require a lot of time and effort from laboratories.  I believe our colleagues in laboratories throughout the forensic community are one of our biggest resources during this process.  I always recommend reaching out to laboratories who have already started the process (including UNTCHI) to see if there is specific advice or resources that they can share.


Why are cross-platform workflows needed within the community?

Laboratories have multiple commercially available massively parallel sequencing platforms to choose from.  The generation of cross-platform workflows allows laboratories who have chosen to implement different platforms to use the same multiplex.  Additionally, cross-platform studies enable us to compare data generated by differing platforms, allowing us to better enable sharing of MPS data generated across the forensic genomics community.


What chemistries and platforms did you evaluate?

This study sequenced PCR products generated by the Promega PowerSeq 46GY kit on both the Verogen MiSeq FGx System and the Ion Torrent Ion S5 System.


What tips would you give to someone who is just starting out in the field of forensics, or what is the best advice that you’ve received?

Always be ready and willing to learn something new.


Has there been anything good that came out of the pandemic that you’ll continue doing going forward?

I believe the pandemic reminded us about all the technologies we have available to connect us with our colleagues both near and far.  I predict we will continue to have many Zoom or Teams meetings in our future.


What is your favorite Disney character and why, or which Disney character do you most relate to and why?

Cinderella was one of my favorite Disney characters growing up and serves as a good reminder to lead with kindness.


If you could have one superpower, what would it be and why?

If I could have one superpower, it likely would be the ability to fly.  To be able to see family and friends with such ease, no matter where they live, would be wonderful.


What’s one thing that others may not know about you?

I would have a house full of dogs and cats if I could! Sadly, my HOA feels I should stop at four.  🙂