Recent global figures indicate that 35% of women worldwide have experienced either intimate partner violence or non-partner sexual violence in their lifetime. Consider the US for example, >293,000 people (age 12 or older) are victims of rape or sexual assault each year-that’s equivalent to 1 victim every 2 minutes.
Unfortunately, samples from sexual assault type cases are among the most difficult sample types encountered by many forensic laboratories.
These samples either have:
– very small quantity of male DNA compared to a high quantity of female DNA
– or they contain multiple male contributors which means complex mixture analysis
To further compound this issue, the steps to achieve a DNA profile are often quite labor- intensive and very time consuming.
Applied Biosystems™ QuantiFiler™ Trio, GlobalFiler™, and Yfiler™ Plus kits offers a streamlined workflow when dealing with challenging DNA mixture samples by helping to maximize information generated on each sample, the first time through the workflow.
In fact, due to the Quantifiler kit’s ability to accurately detect sub picogram levels of DNA in a reproducible manner, labs are now able to use it as an upfront DNA confirmatory screening method to answer the question-
Is there male DNA present or absent?
In as little as 2 hours, forensic scientists will know if they have a viable sexual assault sample for further processing.
Watch the kits in action below:
Once the presence of male DNA is determined, the forensic analyst can proceed further with differential extraction & then quantification. Quantifiler Trio is also great as a decision making tool to determine downstream STR strategy- autosomal or Y. If the male to female ratio is <1:20, autosomal STR analysis is unlikely to return a quality autosomal profile for the minor male contributor. In fact, if the sample was amplified with an autosomal kit, that minor male profile may not even be detected if the female DNA completely overwhelms the male DNA during amplification. In such cases, it is recommended to go with Y-STR analysis using the Yfiler Plus chemistry. This is the first 6 dye, 27-multiplex YSTR kit that has 7 rapidly mutating YSTRs and 11 mini YSTRs for superior discrimination capacity.
In fact, forensic experts, Dr. Lutz Roewer & Dr. Franz Neuhuber delivered a webinar on YSTR analysis to determine:
- What cases are appropriate for Y-STR
- How to interpret Y-STR results
- How to present Y-STR data in court
If you need further information on any product or have a question, reach out at:
For Forensic or Paternity Use Only.