STRmix™. Resolve more DNA mixtures

STRmix™ is expert forensic software that can resolve previously unresolvable mixed DNA profiles. Developed by global leaders in the field, it uses a fully continuous approach for DNA profile interpretation, resolving complex DNA mixtures worldwide.

FAST

STRmix™ interprets complex DNA results in minutes.

ACCESSIBLE

STRmix™ software runs on a user's PC, without the need for high-speed computing.

ENABLING

STRmix™ can be easily understood and explained in court by DNA analysts.

Click here for an overview of STRmix.

STRmix™ is a breakthrough for forensic analysts as it can assist investigations using DNA evidence that was previously considered too complex to interpret. The software has been developed by New Zealand Crown research institute ESR, with Forensic Science South Australia (FSSA).

STRmix™ includes a function that allows the software to match mixed DNA profiles directly against a database. This is a major advance for cases where there are no suspects and there is DNA from multiple contributors in one sample.

With STRmix™ you will be able to:

  • interpret DNA results faster
  • compare profiles against a person of interest and calculate a likelihood ratio
  • resolve previously unresolvable, complex DNA mixtures with no restriction on the number of contributors
  • use more of the information in a DNA profile
  • search complex, mixed DNA profiles against a database.

STRmix™ V2.4 is now available for purchase. Join our database for updates or contact us to request a quote.

WHAT CAN STRmix™ DO?

Resolve mixed DNA profiles  without reference to known contributors.

Compare reference DNA profiles to single source and mixed DNA profiles and provide a statistical weighting.

Interpret DNA profiling data generated by any autosomal STR profiling kit.

Interpret DNA profiles from a range of starting template DNA concentrations.

Use laboratory-specific settings to perform calculations suited exactly for that laboratory’s results.

Search a deconvoluted DNA profile directly against a database without the need to interpret a single source component.

Incorporate multiple EPGs into one analysis.

Accommodate data generated by protocols demonstrating increased stochastic variation and non-zero allelic drop-in rates, for example elevated PCR cycle number and enhanced CE injection methods.

Include related individuals as alternate propositions in the likelihood ratio.

Batch multiple deconvolutions in a queue, allowing the user to run multiple deconvolutions and calculate likelihood ratios sequentially.

Carry out familial searches against a database, searching for close relatives of contributors to mixed DNA profiles.

STRmix IN USE

STRmix™ has already been used for routine casework interpretation at ESR and FSSA since August 2012 and is now the Australasian standard for DNA interpretation.

In one case, a mixed DNA profile was obtained from a semen stain on a carpet at the scene of an alleged sexual assault involving two male offenders. DNA from two individuals was detected, present in approximately equal proportions (see EPG below). This profile was unsuitable for database searching using traditional DNA interpretation methods. Using STRmix™, the profile was interpreted assuming two contributors and compared against a database with over 145,000 profiles. The crime profile matched two individuals.

This case highlights how STRmix™'s database search function can provide investigative information. It can also be used to validate complex mixtures where contamination is suspected.

STRmix™ V2.4 is now available for purchase. Join our database for updates or contact us to request a quote.

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HOW DOES STRmix™ WORK?

STRmix™ software combines biological modelling and mathematical processes to achieve results not possible with traditional DNA interpretation methods.


Using standard and well-established statistical methods, the software analyses a DNA profile and determines which DNA genotypes best explain the data. STRmix™ models the height of both allelic and stutter peaks (both back and forward stutter). Using a Markov Chain Monte Carlo engine allows STRmix™ to rapidly analyse profiles that would otherwise be too complex.


STRmix™ is based on exhaustive biological modelling and its mathematics are accessible to DNA analysts, so results can easily be explained in court.

VALIDATION

STRmix™ has been extensively validated and has been used for casework interpretation at ESR and several Australian and US laboratories (first implemented in August 2012).  STRmix™ has achieved Certificate of Networthiness (CoN) status on the United States Army Network.

PUBLISHED DATA

Papers describing the biological model, mathematics and performance of STRmix™ have been published:

[1] D. Taylor, J.-A. Bright, J. S. Buckleton, The interpretation of single source and mixed DNA profiles, Forensic Science International: Genetics. 7(5) (2013) 516-528.

[2] J.-A. Bright, D. Taylor, J. M. Curran, J. S. Buckleton, Developing allelic and stutter peak height models for a continuous method of DNA interpretation, Forensic Science International: Genetics. 7(2) (2013) 296-304.

[3] J.-A. Bright, D. Taylor, J. Curran, J. Buckleton, Degradation of forensic DNA profiles, Australian Journal of Forensic Sciences. 45(4) (2013) 445-449.

[4] J.-A. Bright, D. Taylor, J. M. Curran, J. S. Buckleton, Searching mixed DNA profiles directly against profile databases Forensic Science International: Genetics. 9 (2014) 102-110.

[5] D. Taylor. Using continuous DNA interpretation methods to revisit likelihood ratio behaviour. Forensic Science International: Genetics, 2014. 11: 144-153.

[6] J.-A. Bright, J.M. Curran and J.S. Buckleton, The effect of the uncertainty in the number of contributors to mixed DNA profiles on profile interpretation. Forensic Science International: Genetics, 2014. 12: 208-214.

[7] J.-A. Bright, I.W. Evett, D. Taylor, J.M. Curran and J.S. Buckleton, A series of recommended tests when validating probabilistic DNA profile interpretation software. Forensic Science International: Genetics, 2015. 14: 125-131.

[8] J.-A. Bright, K.E. Stevenson, J.M. Curran and J.S. Buckleton, The variability in likelihood ratios due to different mechanisms. Forensic Science International: Genetics, 2015. 14:187-190.

[9] D. Taylor, J.-A. Bright and J.S. Buckleton, Considering relatives when assessing the evidential strength of mixed DNA profiles. Forensic Science International: Genetics, 2014. 13: 259-263.

[10] T.W. Bille, S.M. Weitz, M.D. Coble, J.S. Buckleton and J.-A. Bright, Comparison of the performance of different models for the interpretation of low level mixed DNA profiles. Electrophoresis, 2014. 35:3125-33.

[11] D. Taylor, J.-A. Bright and J.S. Buckleton, The ‘factor of two’ issue in mixed DNA profiles. Journal of Theoretical Biology, 2014. 363: p. 300-306.

[12] D. Taylor and J.S. Buckleton, Do low template DNA profiles have useful quantitative data? Forensic Science International: Genetics, 2015. 16:13-6.

[13] D. Taylor, J.S. Buckleton and I. Evett, Testing likelihood ratios produced from complex DNA profiles. Forensic Science International: Genetics, 2015. 16:165-171.

[14] S.J. Cooper, C.E. McGovern, J.-A. Bright, D. Taylor and J.S. Buckleton, Investigating a common approach to DNA profile interpretation using probabilistic software. Forensic Science International: Genetics, 2015. 16:121-131.

HARDWARE SPECIFICATIONS

STRmix™ is designed to run on an individual DNA analyst’s PC (either standalone or in a networked environment), without the need for high speed computing.

Low spec* Medium spec** High spec***
Intel core 2 (Quad core) processor Intel i5, i7 2.6 GHz  Intel 2.4 GHz Xeon CPU E5****
4 GB RAM 16 GB RAM 128 GB RAM
10MB free HDD space  10MB free HDD space 10MB free HDD space
Windows XP Professional Windows 7 Professional 64 bit or above Windows 7 Professional 64 bit or above

* will run most 1, 2 and some 3 person mixtures, particularly in low memory mode, may also run some 4 person cases

**will run most 1, 2, 3 and 4 person mixtures, particularly in low memory mode

***will run most 1,2,3,4 person mixtures (including with replicates) and 5 person mixtures (including with replicates)

****consult with NicheVision/ESR on particular models if concerned. 

SOFTWARE SPECIFICATIONS

Windows XP service pack 2,  Windows Vista service pack 1, Windows 7 service pack 1, Windows 8.1 or Windows 10.
Java version 1.7 or later.

STRmix™ V2.4 is now available for purchase. Join our database for updates or contact us to request a quote.

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WHO DEVELOPED STRmix™?

Institute of Environmental Science and Research (ESR)

ESR uses the power of science to solve complex problems with the potential to affect the lives of all New Zealanders. It is the sole source provider of forensic services to the New Zealand Police while its comprehensive knowledge of the presence and interpretation of DNA is utilised across the country and around the world.

Forensic Science South Australia (FSSA)

FSSA provides independent, objective expert scientific opinions and evidence to the justice system and community of South Australia undertaking a comprehensive range of forensic case work in Pathology, Biology, Toxicology and Chemistry.

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News

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Did you know?

Tuesday, 28 June 2016

Key Forensic Services Limited achieves accreditation for STRmix™

Wednesday, 15 June 2016

STRmix™ developmental validation article accepted in Forensic Science International: Genetics

Monday, 16 May 2016

STRmix™ Training Workshop, 13-15 September, 2016 (3 days), Location: Auckland, New Zealand

Friday, 13 May 2016

STRmix™ attends ENFSI DNA 2016

Friday, 29 April 2016

STRmix™ in the news: Lost shoe led to landmark DNA ruling - and now, nation's 1st guilty verdict

Friday, 29 April 2016

Access to STRmix™ Software by Defence Legal teams

Thursday, 28 April 2016

STRmix™ workshop at 5th QIAGEN International Investigator Forum, June 14-16th 2016, Trump International Beach Resort -Miami

Tuesday, 26 April 2016

STRmix™ in the news: DNA breakthrough: North Adelaide rape suspect arrested

Thursday, 21 April 2016

Misrepresentation of STRmix by Mr Dominic Saraceno ESQ in People of New York v. David Smith

Wednesday, 20 April 2016

Statement on minor miscoding in BN formulae in STRmix v1.08

Wednesday, 20 April 2016

STRmix™ version 2.4 released 7 April 2016

Friday, 8 April 2016

Statement relating to STRmix™ miscodes

Friday, 18 March 2016

STRmix™ Training Workshop, 18-21 October, 2016 (4 days), Location: Montgomery County Police Crime Laboratory

Thursday, 17 March 2016

STRmix™ Training Workshop, 1-4 August, 2016 (4 days), Location: California Department of Justice

Thursday, 17 March 2016

STRmix™ Training Workshop, 19-22 July, 2016 (4 days), Location: Palm Beach County Sheriff's Office

Thursday, 17 March 2016

NIST Inter Laboratory Study 2013

Friday, 24 July 2015

STRmix™ runs for charity

Thursday, 19 March 2015

STRmix™ version 2.3 released 1st February 2015

Monday, 2 February 2015

View the recent "Mixture Monday" web meeting: Discuss Probabilistic Software with John Buckleton

Wednesday, 17 December 2014

NIST Investigation of Probabilistic Software Programs Released

Thursday, 27 November 2014

NicheVision Forensics is now the exclusive STRmix™ distributor for the Americas, including the United States, Canada, Central and South America.

Monday, 6 October 2014

ESR technology being used to solve war crimes

Monday, 6 October 2014

'Dream' software boost power of DNA

Monday, 6 October 2014

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CONTACT

STRmix™ is expert forensic software that can resolve previously unresolvable mixed DNA profiles. Developed by world leaders in the field, it uses a fully continuous approach for DNA profile interpretation, resolving complex DNA mixtures with no restriction on the number of contributors.

For more information about STRmix™ or to request a quote:

Björn Sutherland Forensic Development Manager
Institute of Environmental Science and Research Limited
Private Bag 50348, Porirua 5240, New Zealand
bjorn.sutherland@esr.cri.nz
+64 4 914 0681
+64 27 612 7378

North/South/Central America Distributor
NicheVision Inc.
526 So Main St Ste 714-G, Akron OH 44311, USA
1-866-840-3758 (US Only) or 1-330-252-2711 (International)
Vic Meles
vic@nichevision.com

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