Olli's group was launched on 2020. We are a highly collaborative group of PhD researchers, postdocs, and Master's and Bachelor's students with diverse backgrounds and expertise.
Olli Pietiläinen

I am a group leader in the Neuroscience Center of the Helsinki Institute of Life Science at the University of Helsinki and a visiting researcher at the Stanley Center for Psychiatric Research at the Broad Institute of MIT and Harvard and affiliate senior scientist at the Institute for Molecular Medicine Finland (FIMM). I received my doctorate in molecular genetics at the University of Helsinki. I continued as a Postdoctoral Fellow at  Harvard University with Professor Kevin Eggan (dept. of Stem Cell and Regenerative Biology) and at the Broad Institute. In 2020, I started as a Senior Scientist and a Group Leader at the HILiFE Neuroscience Center, University of Helsinki. An expert in complex disease genetics and functional genomics, I have co-led large patient sample collections and leads the research group for Genomics of Human Brain Disorders.

Nelli Karmila

PhD Researcher

I am a PhD student with an MSc in genetics and molecular biosciences. My research focuses on understanding mechanisms underlying neuronal network defects in schizophrenia. Specifically, I use microfluidic cell cultures for reconstructing neuronal networks in genetically characterized neurons.

In addition, I am currently using the microfluidic devices for studying localized transcriptomics in iPSC-derived neurons. I aim to illuminate the synaptic pathology in schizophrenia.


Emilia Vartiainen

PhD Researcher

I am a doctoral researcher in the Pietiläinen Group, in the doctoral program of Brain and Mind. I hold a master’s degree in bioinformatics and digital health from Aalto University. I am particularly interested in the health implications and biological mechanisms in mental disorders. 

My research focuses in applying computational tools to  explore the clinical and cellular features that correlate with genetic risk for schizophrenia. To achieve this, I utilize clinical register data from the FinnGen study and SUPER study of genetic mechanisms of psychosis in Finland, as well as transcriptomic data from human iPSC-derived neuronal models.

Noora Räsänen

PhD Researcher

I'm a fifth-year PhD student working in collaboration between the groups of Jari Koistinaho and Olli Pietiläinen. My work focuses on studying cellular mechanisms of schizophrenia using human iPSC-derived neurons in co-cultures with astrocytes. I use a neuronal differentiation protocol based on NGN2-overexpression coupled with cortical patterning. These neurons develop functional synapses and network-level activity in co-cultures with human or rodent astrocytes. So far, I have investigated the role of neurons and astrocytes in functional and synapse-related alterations in schizophrenia using patient-derived iPSCs.

Nelli Jalkanen

PhD Researcher

I am a doctoral researcher working with human iPSC-derived neuronal disease modelling of rare intellectual disability and schizophrenia variants identified in the Northern Finnish Intellectual Disability cohort. In my current project I study the role of a transcription modulator gene INTS6 in the cellular pathophysiology of intellectual disability. I use multifaceted approaches, including transcriptomics, functional genomics, and gene editing combined with molecular cell biology to decipher the mechanisms driving defects in gene regulation and their role in neurodevelopmental disorders. 


Iina Sivonen

Ph.D. Researcher

I graduated as MD from the University of Turku, Finland, in spring 2024 with special interested in mental health and psychiatric disorders.

I joined the research group in 2024 and my work focuses on genetic analysis of disease trajectories of psychotic disorders where I combine genetic data with electronic health record information from the Finnish national healthcare system.  My work leverages large national study cohorts and data resources including the SUPER study of genetic etiology of psychotic disorders in Finland, and the FinnGen study combining longitudinal data from over 500 000 individuals.


Kalevi Trontti

Staff Scientist

My background is in genetics and evolutionary biology, and the past ten year I’ve been mainly working in projects focusing on genetic underpinnings of mental disorders, including anxiety, phobias and schizophrenia. I have wide scientific training ranging from wet lab experimental biology and bioinformatics.

I currently focus on bioinformatics and sequence data analysis from single cell and bulk experiments in human iPSC-derived neurons and publicly available data. On the side I also work on genetic analysis using patient cohorts and population data from the FinnGen study. Using genomic readouts from genetically characterized human cells, I aim to discover biological mechanisms of several high-risk variants associated with schizophrenia. The findings from the genomic analysis are followed up in wet-lab experimental biology that provide an excellent counterbalance for my computational work.


Hande Topa [Alumnus]

Postdoctoral Fellow (Alumnus) 

HANDE, a computational scientist with Ph.D. in statistical genetics, focused on RNA- sequence data analysis to understand genomic mechanism of male-female differences in gene expression using data from human induced pluripotent stem cells (hIPSCs) and  derived neuronal cells from over 150 donors.  By applying multifaceted statistical approaches and leveraging the de-repression of X chromosome inactivation that takes place in female hiPSCs, Hande explored the role of the X chromosome in regulating gene expression in autosomes and genes associated with neurodevelopmental disorders.