Nemaline Myopathy group

The TeamAlumni

Katarina Pelin

PI, PhD, Docent

Katarina Pelin, the Principal Investigator, coordinates the scientific efforts of the Research Group on Nemaline Myopathy and Related Disorders, The Folkhälsan Institute of Genetics and Department of Medical Genetics, University of Helsinki, together with her Co-PI Carina Wallgren-Pettersson. Katarina initially joined the group as a postdoctoral researcher in 1996 after receiving her PhD degree from the University of Helsinki. Her first task was to identify the gene causing autosomal recessive nemaline myopathy, which turned out to be the nebulin gene, in which she identified the first disease-causing mutations in 1998. She has been working on the molecular genetics of nemaline myopathy ever since, and in 2012, she became the Co-PI of the group. She also teaches Human Genetics, as a University lecturer since 2003 at the Faculty of Biological and Environmental Sciences at the University of Helsinki.

Carina Wallgren-Pettersson

PI Emerita, MD, Dr. Med. Sci., Docent

Carina Wallgren-Pettersson, together with Katarina, coordinates the work of the research group. Carina is a Medical Doctor specialised in Medical Genetics, working as a clinician and Head of Department at the Folkhälsan Department of Medical Genetics, and as a teacher at the University of Helsinki. Her research has concentrated on neuromuscular disorders, mainly on nemaline myopathy and previously also on myotubular myopathy, and related congenital myopathies. She initiated the ENMC International Consortium on Myotubular Myopathy in 1993 and coordinated its research activities until January 2000. Together with Professor Nigel G. Laing in Perth, Australia, she has been coordinating the activities within the ENMC International Consortium on Nemaline Myopathy since 1996, among other work defining diagnostic criteria and clinical classifications of the nemaline myopathies. Carina initiated the network called the Finnish Neuromuscular Club and was one of the initiators of the Finnish network on muscle disorders in children and, most recently, the European Reference Network NMD-FIN Consortium, now accepted as part of EURO-NMD.

Vilma-Lotta Lehtokari

PhD, Docent, MSc (Nutrition), Senior Scientist

Vilma-Lotta Lehtokari has a BSc degree in engineering in bio- and food technology from the Polytechnic of Espoo-Vantaa (2000). In 1998, she studied at the Cork Institute of Technology as an exchange student. Her studies continued at the University of Jyväskylä, and she received her Master's degree in Biotechnology in 2003. Over the years 2004-2009 Vilma-Lotta worked as a doctoral student in the Wallgren-Pettersson/Pelin lab and defended her doctoral thesis, titled "Molecular genetic studies on nemaline myopathy and related disorders", in June 2009. In 2010 she embarked on her studies in nutritional sciences at the University of Helsinki and received her second Master's degree in 2016. She worked simultaneously as a post-doctoral fellow, doing research into the molecular genetics of nemaline myopathy and related disorders. Vilma-Lotta currently continues her work in Genetics but has also expanded her studies towards the nutrition and functioning of people with muscle disorders.

Jenni Laitila


After graduating from the University of Helsinki in 2009 with a Master's degree in Human Genetics, Jenni Laitila has studied nebulin genetics and function in the Wallgren-Pettersson/Pelin lab and the Laing/Nowak lab in Perth, Western Australia. She has ivenstigated the expression of nebulin RNA in diverse muscles, interactions of the enormous nebulin protein, and effects of mutations in a novel disease model she characterised in Australia as part of her PhD. In September 2019, she defended her Doctoral Dissertation based on her studies of nebulin-related nemaline myopathy. In her postdoc project (2020-2024) she focused on studying myosin dysfunction in NM in the physiology and muscle mechanics research group in Copenhagen, led by Julien Ochala. Currently, she is back in Finland, elucidating the various aspects of muscle function in health and disease, focusing on studying energy consumption and metabolism of single muscle fibers of the patients with neuromuscular disorders. She will continue on the path to unveiling the molecular changes leading to myopathies, aiming at finding potential new targets for therapy.

Fanny Rostedt

MSc, Doctoral Researcher

After completing her master's thesis project in the group, Fanny Rostedt graduated with a Master's degree in Genetics and Molecular Biosciences from the University of Helsinki in June 2023. The same summer she joined her PhD supervisor Jenni Laitila in Julien Ochala's lab at the University of Copenhagen for a one-year visiting research position to learn techniques for analysing single skeletal muscle fibres. For her PhD project she will mainly focus on myosin dysregulation, which is directly linked to energy consumption, in various congenital myopathies.

Milla Laarne

MSc, Doctoral Researcher

Milla Laarne graduated with a Master's degree in Genetics and Molecular Biosciences from the University of Helsinki in June 2022. She completed her Master's thesis work in the RNAcious Laboratory, led by Peter Sarin, and continued to work in the group as a research assistant after graduation. During her time in the RNAcious Lab, she was involved in a project that focuses on the role of tRNA modifications in colorectal cancer. Milla started her PhD in the Wallgren-Petterson/Pelin lab in January 2023. For her PhD project she analyzes whole genome and whole exome sequencing data to find the causative variants behind certain congenital and distal myopathies. She also carries out functional validation of the candidate variants.

Teemu Turku

MSc, Research Assistant

Teemu Turku completed his Master's thesis work in the group and graduated with a Master's degree in Genetics and Molecular Biosciences from the University of Helsinki in April 2024. After graduation, he has continued to analyze next-generation sequencing data of genetic myopathy patients.

Marilotta Turunen

Research Assistant

Kirsi Kiiski

PhD, European Clinical Laboratory Geneticist, Senior Scientist

Kirsi Kiiski has received her Master's degree in Human Genetics from the University of Helsinki in 2007. After that, she worked for three years at the Laboratory of Cytogenetics in Helsinki University Central Hospital, mainly in research and development, to establish and validate molecular karyotyping for routine constitutional diagnostics. From the beginning of 2011, she joined the Wallgren-Pettersson/Pelin research laboratory to work on her PhD. She focused on developing new diagnostic methods such as a targeted custom array-CGH protocol for nemaline myopathy and related muscle disorders, graduating as Licenciate in 2014 and PhD in 2015. At the same time, she completed her clinical training for the Clinical Laboratory Geneticist Degree in the United Medix Laboratories and Helsinki University Central Hospital, receiving the Clinical Laboratory Geneticist Degree in 2014 and an EBMG certified ErCLG Degree in 2016. Kirsi has continued her research in the field of muscle disorders and has acted as a supervisor for MSc and PhD students in the group. Currently, Kirsi works mainly as a CLG and chief of laboratory in the Helsinki University Central Hospital, Laboratory of Genetics. Kirsi focuses on diagnostic genetics in the field of constitutional cytogenetics, molecular cytogenetics and molecular genetics including copy number variant diagnostics but continues her research in the field of muscle disorders part-time in the group, as well.

Lydia Sagath

PhD, Affiliated Postdoctoral Fellow

Currently a Postdoctoral Fellow at Alexander Hoischen's lab, Radboudumc, Nijmegen

After completing her Master's degree in the Udd lab at Folkhälsan Research Center in 2016, Lydia Sagath joined the Wallgren-Pettersson/Pelin lab to embark her studies towards a PhD. Her doctoral work included the development of diagnostic methods for nemaline myopathy and related disorders, such as the targeted custom CGH-array and a novel ddPCR method, and she defended her thesis in June 2022. In addition, she has done functional characterization work with a putative disease-causing gene, and completed part of the project as an ASLA-Fulbright pre-doctoral fellow at the Lange lab at the University of California, San Diego. She defended her Doctoral Dissertation in June 2023 and is currently a Postdoctoral Fellow in Alexander Hoischen's group at Radboudumc, Nijmegen, working with PacBio HiFi data and structural variants in previously unsolved patients.

Johanna Lehtonen

MSc, Affiliated Doctoral Researcher at Janna Saarela's lab, Centre for Molecular Medicine Norway

  • Johanna Lehtonen graduated from the University of Helsinki in 2017 with a Master's degree in Human Genetics. She subsequently started her doctoral studies in the Wallgren-Pettersson/Pelin lab and has also worked at the Institute for Molecular Medicine Finland in the Saarela lab. She has expertise in analyzing high-throughput sequencing data. After concluding an exome or genome analysis interpretation, Johanna studies functionally putative pathogenic variants in the laboratory. She has been working with patient cell lines and various in vitro models. Her research focuses on rare disease genetics, including nemaline myopathy.


    Doctoral dissertations

    • Lydia Sagath
    • Jenni Laitila
    • Kirsi Kiiski
    • Minttu Marttila
    • Vilma-Lotta Lehtokari
    • Kati Donner
    • Carina Wallgren-Pettersson

    Master's thesis

    • Teemu Turku
    • Fanny Rostedt
    • Sampo Koivunen
    • Svetlana Sofieva
    • Giorgia Bennici
    • Johanna Lehtonen
    • Pauliina Repo
    • Jenni Laitila
    • Liina Ahlstén
    • Elina Nuutinen
    • Mutsumi Kellinsalmi
    • Maria Airama
    • Hanna Vidqvist
    • Salla Ranta
    • Vilma-Lotta Lehtokari
    • Miina Ollikainen
    • Kati Donner
    • Pirta Hotulainen

    Past members of the team & visiting researchers

    • Mubashir Hanif
    • Dan Brudzewsky


    Folkhälsan Research Center
    Biomedicum Helsinki
    Haartmaninkatu 8, PB63
    FI-00290 Helsinki

    © Nemaline Myopathy Group 2018-2022