With the 29th International Symposium of Human Identification firmly setting itself on the horizon. Aurora reflected on the past year within DNA forensics. The past year had seen many interesting events; controversial acts being upheld such as California’s ‘DNA on arrestees’ to high profile cases such as the infamous golden state killer being solved via a public genealogy database.
One clear reoccurring theme, however, is the countries turmoil within sexual assault casework sample submission backlogs. Crime laboratories are experiencing new statewide reform and great pressure from social movements to address this. At last year’s ISHI, Aurora sat down with a few of the criminalists at Oakland Police Crime Laboratory to gain more insight into how they have adopted an alternative method of automated differential digestion in order to tackle this.
Jennifer Mihalovich – Technical lead
Chloe – Criminalist II
Laura Silva – Supervisor
1. Could you tell us a bit about what kind of forensic genomic service Oakland PD offers?
JM/LS: Oakland PD has 6 functional units – firearms, crime scene, QA, drug analysis, latent print, biology. Our department is responsible to process specimens from all cases within Oakland jurisdiction and reference samples only for casework, not for databases in jails.
2. Out of all assays you do in your lab, what is the most tedious and time-consuming work for you?
LS: The most time-consuming assay for sure is differential digestion – DNA interpretation is lengthy because it requires focus with the microscope (have to move the slide around and can be tiring for the technician.)
JM: This is a step that is generally done downstream after a sample has been processed. Other parts that are tedious as the extractions; they require manual agitation (annoying step to do with each sample.)
Chloe: All centrifugation needs to be done manually and there are many of these steps in the protocol.
LS: Supervision of the instrument is required on a constant basis (recently gripper wasn’t working) because there could be a malfunction or issue during the sequence.
Chloe: Another step to get rid of was the tedious washing steps with DNAase which is what inspired the protocol that Helena came up with, all staff was involved to help create this protocol but it was Helena who developed it for her Master’s thesis.
3. I see that your lab is using a unique method for handling sexual assault kit and processing differential digestion with coming case samples. Could you tell us how it is different from other commercially available options and how it can be beneficial to the community and other forensic labs?
LS: The reagents used are simple; there are no proprietary reagents used in the protocol.
JM: The validation with automation was a secondary priority but necessary in order to incorporate in our lab.
LS: Erase is a commercially available kit that is similar to our protocol but they use expensive reagents!
4. What brings you to participate in this meeting this year?
JM: This is part of our annual professional development we are required to do. As well I (Jennifer) am presenting my work on testimony and Laura is on a panel to speak about the certification process in forensics.
5. What challenges do you still face within your lab?
JM: We still have a high volume of samples coming through and struggle with getting all the samples through the interpretation and analysis pipelines.
LS: Realistically, we need 10 scientists on staff and require at least 3-4 more people but no space for them. Our lab is very tiny!
6. Out of all the technologies introduced in this event, what interests you the most and why? How do you see that technology being adopted in your lab?
Chloe: I saw the development of messenger RNA for body identification but this is not commercially available for forensics yet.
JM: There are very interesting technologies to determine sample type but it is not relevant to use them in our lab because they are required to produce DNA profiling.
LS: I liked the inject printer to label all samples but I doubt we will be able to get our hands on this!
A special thank you to Jennifer, Chloe & Laura at Oakland for sharing their insights.