New Investigator Amy-Leigh Whittaker on assisting medico-legal investigations in complex inheritance disputes
Amy talks about generating X-STR baseline frequency data for South African populations
September 3, 2020
The new Investigator blog shines a personal spotlight on young scientists and graduate students as they talk about the exciting early stages of a career in human identification and forensics. The passion and commitment revealed in their stories are an inspiration to all in our community.
This new Investigator blog introduces Amy-Leigh Whittaker, a graduate student in the Department of Pathology, University of Cape Town. Amy is working on forensic human identification using X-STRs and establishing baseline haplotype and allele frequencies in South Africans with mixed ancestry.
1. Tell us about your background and how you became interested in forensic science?
I graduated from Stellenbosch University in 2019 with a BSc Human Life Sciences (Cum Laude) majoring in Human Genetics and Physiology. I became particularly interested in forensic science after briefly touching on it during my undergraduate degree. After doing some research, I realized how diverse the field of forensics is: from linking suspects to crimes or exonerating the innocent, to identifying missing individuals or establishing familial relationships. I think that in a country like South Africa, forensic sciences play a big role in bringing justice and closure to both the victims and their families.
2. Can you provide a summary of the project you are working on?
X-STRs have been shown to be useful in deficiency paternity testing and complex kinship testing involving daughters as the X-chromosome is passed from father to daughter unchanged. In South Africa, there is a lack of both X-STR data and allele frequency data from the background population. My project aims to diminish this gap by generating X-STR population data for South Africans of mixed ancestry. This data will be generated for two sample types, extracted DNA and lysates (which make use of a direct PCR approach). Once the X-STR profiles have been generated using PCR and capillary electrophoresis, statistical analyses will be performed on the data. My project also includes an internal validation component of the Investigator Argus X-12 QS Kit.
3. Please describe your typical day in the lab.
I am currently in my first year of postgraduate studies. Therefore, my mornings consist of having lectures and engaging with coursework, while my afternoons are spent working on my research project. Due to the COVID-19 pandemic, I've had to work from home. This has allowed me to plan a lot of the experiments I will be doing once I get back to the lab, e.g., internal validation experiments. I have also spent time becoming familiar with the (free) Arlequin software, which will be used for statistical analyses.
4. What do you find most interesting about your project? Have you seen any surprising results?
Due to the COVID-19 pandemic, lab work has come to a halt. However, we are anticipating finding novel alleles and haplotypes as the South African population is very diverse and under studied.
5. What are the benefits of your project?
My project could be the beginning of possible incorporation of X-STRs in medico-legal investigations in South Africa. This holds great promise in cases where autosomal STRs are not informative enough, such as civil disputes, with specific focus on inheritance disputes which include a deficiency paternity case.
6. What are the major challenges faced while working on your project and how do you overcome them?
Currently the biggest challenge we are facing is the COVID-19 pandemic which has dramatically slowed our progress down. To address this, we are trying to work remotely.
7. Which QIAGEN products do you use and what do you like about the products?
One of the QIAGEN products I use is the Investigator Argus X-12 QS Kit. This kit is useful as it allows for the simultaneous amplification of multiple X-STR markers. Another nice aspect of this kit is the quality measures it includes such as the Quality Sensor, helpful in monitoring PCR success, and an autosomal marker to facilitate alignment to autosomal STR profiles. Another QIAGEN product I have used is the Lysis Buffer in the Investigator Casework GO! Kit. I like this product as lysate samples can be prepared within 5 minutes to allow for direct PCR. This minimizes the laborious process of traditional sample preparation.
8. Outside of forensic science, what are your hobbies?
I am extremely passionate about animals and often use my spare time visiting animal shelters and/or fostering kittens. I also enjoy the outdoors.