Mia Petljak | Former Postdoctoral Fellow at the Sanger Institute

This person is a member of Sanger Institute Alumni.

Petljak, Mia

Mia uses DNA sequencing to identify active mutational processes in human cancer, study their occurrence and explore their underlying mechanisms. Ultimately, an understanding of on-going mutagenesis offers the potential to identify novel therapeutic targets and biomarkers for prognosis and therapeutic sensitivity in cancer patients.

Mia is a PhD student with Mike Stratton within the Cancer Genome Project. She obtained a BSc (Honours and Dean's Distinction) in Human Genetics from University College London in 2012 and subsequently joined the University of Cambridge and Wellcome Trust Sanger Institute for her post-graduate studies. She is co-supervised by Serena Nik-Zainal and works in close collaboration with her team and Ludmil Alexandrov at Los Alamos National Laboratory.

During our lives our DNA is exposed to different sources of DNA damage. Causes of the DNA damage can be of an external and intrinsic origins, such as exposure to UV-light or defects in DNA-repair processes, respectively. The damage that remains unrepaired is embedded within DNA in the form of mutations and can be identified by DNA sequencing. Every cancer cell carries a large number of mutations that are not implicated in oncogenesis but form characteristic patterns termed mutational signatures, which can inform on the sources of mutagenesis. Whereas mutations found in cancer DNA represent historical traces of mutational processes that were once operative, they lack the information on whether the mutagenesis remains switched ‘on’ or ‘off’ in cancer cells.

I am using mutational signatures as a readout, and next-generation sequencing as a tool, to identify mutagenic activities that continue to operate during cancer development and progression. My further interests encompass identification of genes responsible for an active mutagenesis through application of CRISPR/Cas9 genome editing technology.


  • Somatic mutations reveal asymmetric cellular dynamics in the early human embryo.

    Ju YS, Martincorena I, Gerstung M, Petljak M, Alexandrov LB et al.

    Nature 2017;543;7647;714-718

  • Genome-wide chemical mutagenesis screens allow unbiased saturation of the cancer genome and identification of drug resistance mutations.

    Brammeld JS, Petljak M, Martincorena I, Williams SP, Alonso LG et al.

    Genome research 2017;27;4;613-625

  • Understanding mutagenesis through delineation of mutational signatures in human cancer.

    Petljak M and Alexandrov LB

    Carcinogenesis 2016;37;6;531-40

  • Germline TERT promoter mutations are rare in familial melanoma.

    Harland M, Petljak M, Robles-Espinoza CD, Ding Z, Gruis NA et al.

    Familial cancer 2016;15;1;139-44

  • Genome sequencing of normal cells reveals developmental lineages and mutational processes.

    Behjati S, Huch M, van Boxtel R, Karthaus W, Wedge DC et al.

    Nature 2014;513;7518;422-425

  • Association of a germline copy number polymorphism of APOBEC3A and APOBEC3B with burden of putative APOBEC-dependent mutations in breast cancer.

    Nik-Zainal S, Wedge DC, Alexandrov LB, Petljak M, Butler AP et al.

    Nature genetics 2014;46;5;487-91

  • POT1 loss-of-function variants predispose to familial melanoma.

    Robles-Espinoza CD, Harland M, Ramsay AJ, Aoude LG, Quesada V et al.

    Nature genetics 2014;46;5;478-481

Petljak, Mia
Mia's Timeline

University of Cambridge | WTSI PhD Studentship

University College London | BSc Human Genetics


MRC LMCB | Thesis with Prof Alison Lloyd

Technical University Munich | Internship with Prof Florian Greten

Amgen Scholars Studentship | Award


Max Planck Institute | Internship with Prof Nediljko Budisa